Sunday, December 30, 2012

Sometimes you need to tell yourself to just go for it.

I'm naturally introverted and a bit of a perfectionist and there have been several times in my academic career when I was forced to overcome my anxieties, from difficult exams to public speaking. Often the only way to get through these uncomfortable situations was to just suck it up and try my best.

There's a saying that goes: The things that make you nervous in life are the things you should be doing. Often the most nerve-wracking experiences end up being the most rewarding.

If you're nervous about anything in life, just channel the courage of this 4th grade girl taking her first ski jump. (This is several months old but I still love it.)


"Here goes something... I guess..."

Thursday, December 27, 2012

If you ever wanted to know about laser diodes

Nature Photonics wrote up a nice little article about the 50th anniversary of the laser diode last month, not to be confused with the 50th anniversary of the laser which happened in 2010.

I know a lot about laser diodes. I sometimes feel I don't know nearly enough to be considered an expert, but I did co-author a book chapter and write a 210 page dissertation on my 5+ years designing and fabricating visible wavelength laser diodes, so I guess you could say that qualifies me to speak intelligently on the subject.

Still, when people ask me about my dissertation research, I struggle to explain it every time. Not many people know what a semiconductor is or what a laser diode is, or worse, they think they do but they don't. Laser diodes in particular are a source of confusion.

The problem is that in order to understand my research project you need to understand some basic principles on solid state physics and crystallography, in addition to knowing what a laser diode is. They're not exactly simple concepts.

In honor of the golden anniversary of the laser diode, I will finally attempt to explain what they are in simple terms. Behold!


What laser diodes are NOT

Most people hear the word "laser" and picture a huge death ray like in Goldfinger.

Still from laser scene in Goldfinger where Bond nearly nearly gets vaporized junk-first via http://www.cultureblues.com

They imagine I sit in a dimly lit lab, shooting high power laser beams all over and taking scientific measurements on them all day.

High power laser in "Military laser experiment" via Wikipedia

Once in a while, some wise-guy will make an Austin Powers reference about putting them on sharks. This joke got old really fast.




Alternatively, if they were alive in the 80's, someone might make a Real Genius joke about working with Lazlo or making popcorn, but this joke doesn't bother me as much because I love this movie.

"Real Genius" laser lab, via AMC blog

I used the word "optoelectronics" once to describe my area of research, which is a general term describing electrically-injected light emitters like laser diodes, and someone assumed that meant I worked on robotic eyeballs. Like in The Terminator, perhaps?

Arnold's robot eyes may be included under the umbrella of optoelectronics since it probably includes a photodiode. IMG via 13point7billion

To make things easier, most of the time I don't bother mentioning laser diodes at all and just tell people I work on LEDs instead. I occasionally work with LEDs and have many coworkers who specialize in them, so I happen to know a lot about them. Plus, there's that huge benefit of most people having a general idea of what LEDs are and what they're used for. My Grandma might think I make Christmas lights for a living, but I just decided that it's close enough.

LED lights via Apartment Therapy


What laser diodes are

They're really small.
You literally need a microscope to see them. Typical dimensions of the lasers I work with are about one millimeter long and less than fifty microns wide, about the width of a human hair.

Here is a picture of a generic laser diode chip on the head of a needle.  The actual laser is a very thin stripe of metal running vertically down the center of the chip. You may need to view the image at full resolution to really see it.  via Wikipedia
Packaged green laser diode from European lighting giants OSRAM via Semiconductor Today. The rectangular chip is emitting green light, although it's difficult to see the actual laser beam. The wire bonds are used to inject current through the device.
Fully packaged blue laser diodes from Sanyo. The scale is in mm.  


They're basically a glorified LED. 
Light-emitting diodes (LEDs) and laser diodes both have the essential features of diodes, which means they flow current when you apply a voltage.

To be specific, the LEDs and laser diodes I work with are p-n junction diodes. For these kinds of diodes we use a process called doping to turn a semiconductor material into n-type cathode material (more electrons) and p-type anode material (less electrons) and put them together like a sandwich.

Here's Collin Cunningham of MAKE magazine talking about the history of diodes, including the p-n junction diode.

In addition to being diodes, LEDs and laser diodes both produce light via similar magical mechanisms of quantum physics. This magic is contained in a layer in the middle of the p-n junction that has the ability to emit light. This light-emitting layer is also called the active region.

Apply a voltage to a regular diode, the current flows from anode to cathode. But if you insert this light-emitting layer in the middle, when the electrons try to flow through it they magically transform into photons. (In fact, this layer simply traps the electrons and they emit light as a way to lose excess energy, but that's a whole other story for another time.)

One obvious difference between LEDs and laser diodes are their dimensions at the chip level. An LED chip or "die" is usually larger, square, and mostly emits light from the top.

Generic square LED. Current flows from anode to cathode via a transparent contact and wire bond on the top of the sample and a contact at the bottom of the sample (not shown). The light generated in the magic light-emitting layer (a.k.a. the active region) and shines out the top of the sample. LED sizes vary but they are usually less than a mm wide.    
On the other hand, a laser diode is long and skinny and emits a concentrated beam of light from the edge.

Generic edge-emitting laser diode. Like an LED, current flows from anode to cathode via a skinny metal contact and wire bond on the top of the sample and a contact at the bottom of the sample (not shown)The light generated in the magic light-emitting layer (a.k.a. the active region) shines out of the edge of the sample (technically both edges). In this example, only the area under the narrow metal contact of the anode generates current to produce the light which forms the laser beam.
Keep in mind there are MANY different configurations of LEDs and laser diodes and I'm glossing over some other details, but these are just generalizations for simplicity sake.


They have all the necessary components of an actual laser. 
That is to say that although laser diodes are small, they are still technically lasers and produce a tiny laser beam of light via the same mechanisms that all lasers operate.

A few essential features of a laser:
  • It is made from a material that can generate light via energy supplied from an external source (such as an applied voltage which causes current to flow through a magic light-emitting layer, in the case of a laser diode).
  • The light is trapped in a cavity that allows the light to bounce back and forth inside.  
  • Light begets light.

The reason lasers are long and skinny is because the light inside only needs to bounce back and forth in one direction. In our lasers, we trap the light in this long, skinny cavity by forming a thin ridge of metal via photolithography and coating the ends (or facets) with partially reflective mirror material.

If you trap enough light in this long skinny cavity, the material within it-- which is already generating light-- can absorb more energy from the light that it itself created. This is how light begets light. When light begets light you have gain. This gain process is also called stimulated emissionIt's something laser diodes do and LEDs do not.


Henry at Minute Physics explains gain & how lasers work

When you have this gain process happening within a laser, a funny thing happens to the light. This is the magic of lasers. The light gets really narrow in shape, forming a beam, and narrow in spectral width, which means it's all the same specific wavelength or color. Without the benefit of gain and stimulated emission, LEDs produce a much broader color output-- so an LED giving off blue light also gives off a little violet and green as well, but laser diode giving off blue light is a really specific color blue.

Here's Bill Hammack of the Engineer Guy describing how a ruby laser works.


To summarize:
LEDs and laser diodes both flow current when you apply a voltage, and both magically produce light when the current flows through a layer called the active region. A laser diode is long and skinny and when enough light builds up, it magically forms a laser beam.

The "magic" is actually quantum physics and well understood. If you're interested, I may post about it in the future. But, to be blunt, if you're really into this stuff perhaps you should have taken more physics in school. :)


What are laser diodes used for?
OK, so we have some idea what they are and how they work, but why do they exist?  Well, we can thank laser diodes for the following things:
  • Fiber optic data transmission aka THE INTERNET - all your internet is transferred to your computer via laser diodes pulsing light through fiber optics all over the world, even under water, across oceans. To this day, that blows my mind. Even if you're on wireless network, your internet first goes through a physical optical fiber to a router which then rebroadcasts it. (Watch Engineer Guy explain how fiber optic cables work.)
  • CD and DVD technology - use red laser diodes to read and write data on disks.
  • Blu-Ray technology - uses violet laser diodes to do the same thing, but since it has a shorter wavelength than red, that allows higher density of data per disk
  • Laser printing like LaserJet and digital photocopiers - uses IR (invisible) laser diodes to charge a rotating drum which then attracts toner/ink and rolls it onto paper.  
  • Bar-code readers - the thing that goes bloop when you buy things in a store.
  • Laser pointers - do NOT shine them at airplanes.
  • Laser-based projectors - you could use red, green and blue lasers to produce full color images that are always in focus. They are small and lightweight, you could even embed them in a cellphone.

What my dissertation was about
I grew the semiconductor layers (the anode, cathode, and magic light-emitting layer) and then fabricated them into tiny lasers and tested them in a lab. I spent a lot of time improving the growth, design and fabrication of the lasers, which meant working in several labs, including a lab where we grow semiconductor material via a process called metal organic chemical vapor deposition as well as a cleanroom to form the ridge and metal parts. I did not sit in a room full of lasers all day, although once in a while I sat in a room with a microscope and tested really really tiny ones.

The whole point of my project was to show that the particular properties of the particular semiconductor I was working with could make more efficient laser diodes. Oh, and my lasers happened to be blue.

Fun fact: This blog is named "My Laser Boyfriend" after an old joke about spending too much time making lasers and not enough time dating. But such is grad school. 

Wednesday, December 19, 2012

Organic LEDs

Lighting giants Philips showing off some OLED panels, part of a new product line called Lumiblade.



What is an OLED?
OLED stands for organic LED, which uses carbon-containing organic materials as the light-emitting regions of a diode, as opposed to a regular inorganic LED which uses solid semiconductor layers throughout.  The organic materials may consist of small molecules, phosphorescent materials, or electroluminescent polymers, such as polyfluorene, which have the ability to emit light when injected with electrical current.

Organic layers underneath a transparent cathode from HowStuffWorks

To be honest, organic chemistry is completely foreign to me, but the essential features of these materials is that when electrons get inside them and then lose energy, that energy takes the form of visible light.


Advantages of OLEDs
A benefit of OLEDs is that the light-emitting organic material may be coated onto large areas and flexible surfaces. Since some of these organic materials come in liquid form, the coating and processing could be done quickly and easily through processes such as inkjet or screen printing.

OLEDs on flexible substrate, via GadgetVenue

Also, the light generated from an OLED is naturally diffuse and evenly distributed across the entire surface. For regular LEDs, the same result would require many individual LED elements plus diffusers or other optical elements to spread out the light.  

Because the OLED panels may be scaled to size, and because they are so thin and lightweight, it makes them ideal for portable device displays such as cellphones and digital picture frames. Samsung employs a matrix of RGB OLED arrays for its Galaxy phone line, which they call AMOLED (active matrix organic light emitting diode).

Nexus One smartphone AMOLED via Wikipedia


Disadvantages of OLEDs
The biggest drawback of OLEDs is they are less efficient compared to inorganic semiconductor-based LEDs, don't last as long, and are still very expensive to produce. Because of this, they will likely never replace regular LEDs for most lighting applications.

But hey, they sure do look cool!  Just ask the Black Eyed Peas, or these guys:

OLED Xmas tree from the Advanced Technology group at GE 

You can buy Lumiblade panels here.
If you're really DIY, play with your own monochrome OLED display from Adafruit.

Monday, December 10, 2012

Festival of Light Emitting Diodes

Approximately one year ago, I was in Lyon, France to present at Forum LED, a European lighting conference that attempts to bring together science and industry of the LED world.  It turned out to be heavy on the industry and light on the science, so I felt a bit out of my element.

My session chair emailed me the day before my talk to suggest: "I am still wondering if you should not alleviate the scientific content on your talk? Don't you think?" I did, and it was probably a good exercise to lighten my usual research-heavy presentation for a more general audience. It went fine. The conference was interesting overall and gave me the chance to learn some of the challenges for implementing LEDs into the real world.

At my advisors suggestion, I allowed myself time for extra travelling before and after the two-day conference, which went surprisingly well considering I don't speak a lick of French. At times, traveling solo felt humiliating and lonely, but for the most part I enjoyed tromping around on my own and sight-seeing, especially since the LED conference happened to overlap with Lyon's Fete des Lumieres, or Festival of Lights. Which, happily enough, employed lots of LEDs!



These videos give only a small taste of what the experience was like. All over town, buildings are lit up at night with lights and projected animation shows. They closed several streets from traffic to allow thousands (millions?) of visitors to wander around and gape at all the displays. All in one weekend in December. Pretty amazing!



Other lessons I learned on this trip:
  • Look up the maximum hotel per diem rate before booking a room at the conference hotel.
  • Dragging a roller-suitcase through cobblestone is really tiring.
  • If it's going to be raining, bring leather boots and lots of extra socks.
  • Bubble baths RULE, especially when you've done said tromping around in said cobblestone in said boots and rain all day.
  • Jet lag sucks. 
  • 24 hour room service RULES.
  • Trains ALSO RULE.
  • When you're at a conference and don't know anyone there and are socially awkward, it's ok to skip the official conference banquet and take yourself out for a nice dinner instead.

Sunday, December 2, 2012

My Laser Boyfriend's Grad School Survival Guide: How to make the most of the worst* four to seven years of your life

* not actually the worst although sometimes it can feel that way.

“Knowing What I Know Now” 

Surviving grad school was the hardest yet most rewarding thing I've ever done. I pushed myself harder than I ever imagined and experienced some of my lowest lows, but I also had some amazing opportunities, learned a lot, and grew more confident as a scientist and researcher. I also drank. A lot.

Although I had to endure what felt like utter misery at times to get where I am now, going to grad school was still the best decision I ever made.

This fall, my research group took on several new grad students. Seeing them with that "I have no idea what's going on" look on their faces makes me remember how hard it was to come to grad school, not knowing what to expect, and feeling very overwhelmed and out of place.

Since I noticed other science bloggers writing advice for those at younger stages in their career, and I'm at a point in my career that I have some to give, I thought I'd compile some tips of my own for those embarking on an advanced degree in STEM.

Prepare to feel stupid (again). 
Remember the end of high school when you thought you were so smart for getting into college, but then you actually GOT to college and realized EVERYONE was smart, and you had to work your ass off just to stay slightly ahead of the curve? Yeah. Grad school is going to be a lot more of that. But worse.

For me, that first year of graduate coursework was brutal. 

It's good to keep in mind everyone in your graduate program comes from different backgrounds and has different abilities, so don't feel down on yourself if you're not as strong in some areas. (See section on "Impostor syndrome..." below).  This can be especially difficult of you switched majors between undergrad to grad school.

If the graduate coursework is slowing you down, consider take a few undergrad-level classes to refresh on prerequisites. Also form study groups (see section on "Making friends.." below). Also realize that once you're into the Ph.D. program, your actual GPA may not matter as much as it did in undergrad, although this may depend on your department. Often, the publishing and research aspect of your graduate degree is much more important.

When you join a research group it's easy to feel overwhelmed if you don't have hands-on experience. This can be totally OK as long as you're up-front about your abilities and get properly trained. See section on finding a lab mentor below.

Know what you're getting into.
This is basically impossible, but try. Talk to as many people and do as much background research on the department and research group as you can. Do NOT depend on their website for information on current projects or even current group members-- they are often horribly out of date.

Visit the campus, meet with your potential PI one-on-one to discuss possible research projects and funding opportunities, but also ask to get a lab tour from a postdoc or current grad student, then pick their brain for more details. Ask questions like: what's the reputation of this PI compared to others in the department; how involved is the PI in the goings-on in lab; how is the group hierarchy organized; who provides training to new students; what are the expectations of group members in terms of balancing classwork, lab-work, and publishing papers; are there weekly meetings; will you get to travel to conferences, etc.

Know what will or will not work for you. 
...especially in terms of your potential research group and how it operates.

Be aware of how much direction you need and how much you should expect to get. My PI was very hands-off.  I've seen independent, self-motivated students work hard and be very successful with little input, while many other students flounder without consistent feedback and encouragement and end up wasting a lot of time being unhappy and unproductive. On the other hand, I've known other PIs who are overly demanding and constantly meddle, so students who prefer to work independently and at their own pace do not do well under those conditions either.

The grad school lifestyle varies depending on school, department, and especially the PI in charge. If you're older, married, have a family and can't work weekends for example, make that known up-front.

Make friends with other new grad students right away. 
Form study groups with classmates to get through impossible homework sets together. You will naturally bond over the shared experiences of painful grad classes and the awkwardness of being the new kid in your research group. There's a good chance most of you moved from far away and won't have a social group yet, so it can be fun to organize group outings to see more of the town, even if (especially if) this mostly entails beer.

Over the course of your grad career you may eventually lose touch with your friends from your first year, especially if they work in a different lab as you, but they may come in handy down the road when you need to borrow some lab equipment or need advice on something they're expert on. Networking works!

Find a lab mentor ASAP. 
When you first join a research lab, you won't know how to do anything. That's okay. That's expected. Your job in the beginning is to learn and ask questions. You may need to turn to an older grad student, postdoc, or project scientist for advice and specific training. Some groups are better at coordinating this than others, so ask around.

Don't be discouraged if senior grad students don't have much time to give you, especially if they're close to graduating. If you can't find one person, try to reach out to several at once.

Believe me, you will need to earn the trust of the senior researchers in your group. Definitely get on their good side. Make appointments with them, show up on time, ask a lot of questions and write everything down, especially when they train you on equipment. The quicker you learn, and the more effective you are at completing tasks they give you, the sooner you'll get a good project. Your PI trusts these guys, and believe me that they can determine your fate. I've seen it happen.

Be nice to the lab techs and engineers.
They may not have a Ph.D. behind their name, but they have been there longer than you, and know more than you will ever know about the equipment and how things operate. The lab would not run if it weren't for them, so always do what they say.

If you break something, which you will, or have a problem in the lab, which you will, report it right away. Then thank them for fixing it. The more respectful you are to the technicians, the more helpful they may be in the future when you encounter another problem. They can also be a great source of gossip and hilarious stories of other grad students doing dumb things in the lab.

And you know what? Being friendly with technicians is a really important skill to have if you ever get a job in the real world. Because these are the guys you'll be working with every day in industry.

Don't let the grunt work drag you down. 
Thomas Edison said: "Genius is one percent inspiration, ninety-nine percent perspiration." A good research project will not necessarily fall in your lap and you may need to earn your stripes doing someone else's busy work for a while. Be patient. This is how things work in grad school.

Patience is definitely an important virtue. Even when you have your own project, parts of it will be slow and painful and you'll start wondering if this what you really want out of life. Relax. This is science. Sometimes it is boring and soul-sucking, but it will not be like that forever. (See section "Keep Your Eye On The Prize," below) 

Impostor syndrome is a real thing.
There may be times when you feel overwhelmed and that you don't belong. Most people go through this at some point or another. What separates the women from the girls is finding a way to be self-motivated even when every fiber of your being wants to give up.

I often think of Woody Allen quote: "80 percent of success is showing up." When it gets hard, call mom, have a good cry if you need it, but then suck it up and keep going. Sometimes you might feel like you have to work a little harder to keep up with everyone else, and if that's the case, do it. Do it like you have something to prove.

It's important to remember that you were smart enough to get into grad school, you deserve to be here. Besides, no one said it would be easy. If grad school was easy, they wouldn't call us a doctor afterwards. Right?


Learn to budget your time. 
Find a way to manage your schedule. I use Google calendar and have separate calendars for different purposes, even a shared group calendar for meetings and seminars I share with members of my lab. I was so busy by the end of my grad program that I'd forget to make time for lunch if I didn't specifically schedule it in. I rely on my calendar for my daily to-do list because I found I'm more likely to remember to do something if it's in my calendar, even small stuff like "email back collaborator" or "submit purchase order."


Be organized and consistent. 
Come up with a system for naming and storing samples, lab notebooks, and data files, and stick with it. Consistency is key here. If you have a good organization system, it will be no problem find a sample or data quickly. For me it became really useful when I was writing a paper or my dissertation and had to dig up old data to replot or old samples to remeasure.  It was also useful when a younger student or collaborator had a use for some samples I previously thought were worthless.

I learned some lessons the hard way. Every time I got lazy and made a short nickname for a sample instead of using the full sample name, I'd end up regretting it later when I needed to look up the data or find the sample again. Every time I was too busy to file samples away properly and let them pile up on my desk, I'd be totally overwhelmed with the task later. If I didn't type up what I had done in the lab, such as some data I took, I'd forget it even happened.

Write down everything. Take detailed notes in your lab notebook and then transcribe them into a spreadsheet on your computer afterward. This sounds ridiculous but you won't believe how much data piles up over the course of a few years.

Put some effort in the beginning to makes things easier for yourself.

Keep an outline of your dissertation on a file somewhere.
In the beginning you may only have a vague idea of what the title will be. Fill that in first. Check back every few months. Add background information. When your research project becomes better defined, you will be able to add chapter titles, and then subsections. It is a good way to track your progress and can eventually serve as a to-do list. This is also useful when your research project is at a stand-still and you need busy work.

Keep an updated CV/resume on a file somewhere.
This is satisfying to update every time you publish or co-author papers, or present at a conference. It's also fun to work on whenever you're feeling completely disillusioned by grad school and day-dream about getting a real job.  :)

Back up your computer. 
Use online storage like Google Drive or Dropbox in addition to an external harddrive that does automated backups. Seriously. You can not afford to lose your data! Also, get a good anti-virus software and make sure it's up to date. Our lab computers are always infected with some weird virus transmitted through flash thumb drives, so I'm super careful about running automated scans on my stuff. You can never be too careful.

I speak from some experience here, as I lost my entire harddrive due to a nasty virus during my second year of research. It put me back a whole month. 

If you see something that needs fixing, fix it. 
Sometimes it's up to a grad student to step up and volunteer to update the contact information on the group website, or form a journal club, or decide to clean the lab. Be proactive. Don't be one of those guys who sits around and complains about the state of things but never does anything about it. Nobody likes that guy. If something bothers you, change it. If you can't do it yourself, find someone who will. Sometimes being a productive researcher is knowing the right people to talk to in order to get things done.

Grad school has its ups and downs, make the most of it.
Research is especially up and down. If you're in a lull period or otherwise being completely unproductive in the lab, use the opportunity to catch up on journal reading or cleaning your desk. Or, fuck it, just go home and use your time to do something useful there like grocery shopping or laundry. Catch up on life stuff. When you're in a major crunch period and pulling long hours, which will happen, you won't have time for life stuff. Go to the store and stock up on soup and trail mix for those times you get sucked into studying, writing, or lab-work and don't have time to go shopping.

Know your limits, mentally and physically.
It's easy to lose touch with the most basic needs when you're busy and under a lot of pressure. It's important to stay productive when you need to be, so do everything possible to foster an environment that helps you towards this goal. Know yourself. If you get easily cold, keep a sweater in the lab. If you're irritable when you're hungry, keep snacks in your desk drawer. If you're sleepy and unmotivated, go grab a coffee. If you're stressed and antsy, take a break and go for a walk, or take up a soothing hobby like knitting. If you need 9 hours of sleep every night and exercise every day, make time for that.

If you're overwhelmed, anxious or depressed and it's affecting your work, consider counseling. Many schools have mental health services filled with people whose job is to offer helpful advice when you're going through a stressful period. I've been to counseling off and on during grad school and it helped a lot (a bad break-up; preparing for, failing, then preparing again for my Ph.D. entrance exams...). It's not an admission of failure to seek help, it's being proactive. 

Side-note: I've found not all therapy techniques are useful. I've gained a lot from cognitive behavioral approach, which suggests that negative feelings of anxiety and depression are related and stem from negative self-talk and distorted thinking. I learned a lot from examples and exercises in the Feeling Good Handbook by Dr. David Burns. (Sorry to sound like an advert, this just worked for me!)

Don't compare yourself to others.
Don't compare yourself to the golden-boy grad student who manages to crank out way more papers than everyone else, and especially not those friends of yours who got a great job after undergrad, are earning tons more money, getting married and having babies. Whenever you compare yourself to others, especially those buying BMWs and posting pictures of it on Facebook, you will feel depressed and it will seem like you're wasting your life inside a research lab.

Don't lose your sense of self in the bubble of grad school. Trust me, there's nothing like graduate school to make smart, motivated people feel stupid and lazy. From the outside, you're doing great things. Make some non-grad student friends or consider getting involved in outreach opportunities in the community to help you gain perspective.

Keep your eye on the prize. 
Don't forget the whole point of grad school is to graduate. If you feel you're not making progress towards this goal, take a step back and assess the situation. If you feel helpless, realize it's okay to ask for help. You shouldn't be expected to be a perfect scientist, you are here to learn to become one.

Are you stuck? Is your stuff simply not working? Are you waiting on something completely outside of your control that's preventing you from making progress and it's taking so long that you're going out of your mind with boredom? Maybe you need to back up and approach it in a new way. Talk to your advisor about starting a side project or collaborating with someone new.

Did you get wrapped up in a side project that's been distracting you for too long and you aren't making any progress on your main project? Figure out a way to put it on the back burner or delegate it to someone else so you can focus your energy on more important things.

Be nice to the first year grad students. 
Mentor them. Advise them. Train them. Take advantage of their naiveté and give them some of your busy work. Remember your first year as a grad student , and how happy you were to finally do something on your own in lab? Don't think that spending time training others is a huge inconvenience, they may end up being really helpful. Don't pity them, either. It's the circle of life. Grad school life. (Whatever that means!)

Sunday, November 25, 2012

Do one thing. Do it better than anyone else.

Man and Beast is a beautiful dramatization about the early life of zoologist and activist Alan Rabinowitz. In the short film, which Rabinowitz himself narrates, he describes how he overcame a childhood speech disorder and how his love of animals and science lead him to apply to graduate school and eventually become a leading expert and activist for endangered species.


MAN AND BEAST from peter simonite on Vimeo.


I don't know any scientist who wasn't into science as a kid. Yet, when you're entrenched in what feels like the unending servitude of academic research, it's easy to lose touch of what inspired you to pursue an advanced degree in science in the first place. It may also be easy to bog yourself down with anxiety and uncertainty of what might come of it, post-PhD...

Why do I always say 'you' when I mean 'me'?

Dr. Rabinowitz is the CEO of the conservation organization Panthera and has published several books and won many awards for his work protecting large cats in particular.

Watch his interview on Colbert Report. Definitely inspirational.

Tuesday, November 20, 2012

Kickstarter LED bulbs and why they probably suck (sorry)

This LIFX Kickstarter project got a lot of blogosphere buzz back in mid-September. In their video, the LIFX team promises a "reinvented" lightbulb -- an energy efficient LED-based bulb that you can dim and color tune via a smartphone app.



The project reached $1.3 million in donations, an order of magnitude greater than their goal of $100,000, before Kickstarter intervened and capped it. In fact, the project was the center of so much buzz and controversy, Kickstarter was forced to impose new rules on raising funds for products that don't actually exist yet.

Yet, despite skepticism they will meet their shipping goals, the Lifx was successfully funded five days ago and are still scheculed to ship in March. According to their Kickstarter updates, they plan to have their first prototype in 4-6 weeks. 

Now Kickstarter has Light by Moore's Cloud, which is kind of the same thing, only more of a dimly glowing orb than a bulb replacement. They are only $170 thousand towards their goal of $700 thousand with 30 days to go.

It leaves people wondering: has Kickstarter turned into a Skymall for vaporware?

More importantly, are these products solving a problem that exists?  Never in my life have I sat in my apartment and thought, "I wish the light in here was more purple." Plus, looking for my phone and firing up some app to adjust the lights in the room seems more annoying than just getting up and turning on a light switch. To me these products seem like gimmicky, glorified party lights.

Yet, I will admit that color tuning may be the future of lighting. We are beginning to understand the relationship of light and color and human health, and how gradual changes in color and intensity may aid the wake-sleep cycle.

Also, a wifi-enabled smart-phone gadget that demonstrates the adaptability of LEDs is great for showcasing their capabilities. And it's good news for LED makers that people are eager to get behind these projects, because it means they're willing to shell out >$50 for a tricked-out LED bulb.

Unfortunately, I'm fairly certain the Lifx bulbs will suck. I'd love for these guys to show me their spec. sheet of their final product and prove me wrong, but I'd be willing to bet they will be (a) not very bright, (b) not as energy efficient as it claims (of which they are vague about) and, (c) the quality of light it emits will be disappointing. The bulb doesn't even appear to have an option for regular warm white.

There are a metric shit ton of ways LED makers describe and measure the efficiency and quality light from an LED bulb, including the brightness, ability to render colors (skin tones look like skin tones, reds look red), and color temperature or "warmth" of the light. Researchers and developers have been working for years and spending many millions of dollars to create beautiful, warm white light from an LED bulb that is more energy efficient and as bright as a compact fluorescent and standard incandescent.

It's not an easy problem to solve. In fact, it took three years for anyone to meet the Department of Energy's guidelines for an LED-based incandescent replacement bulb. The only company to achieve those goals and win the $10 million prize was a multibillion dollar lighting company, Philips Lighting USA. The prize was awarded only one year ago and it is rumored that the prize money didn't even cover their development costs. Their award-winning (just white) bulbs hit store shelves this past April, and still cost around $30 each.

How many PhDs does it take to design a lightbulb? A LOT. (Trust me, don't get any of them started on the mechanisms behind efficiency droop.) Those of us involved in solid-state lighting research are still trying to understand basic science behind diode-emitters in order to increase lumens per watt at the chip level. At the consumer product level, reducing production costs remains the biggest challenge. And the Lifx team thought they could get away with development costs of merely $100,000? Bitch, please.

The final blow is the LED giants at Philips have just released Hue, which hit the markets in October. Like the Lifx, these bulbs can adjust color and intensity via a wifi-enabled app. They also have the benefit of ACTUALLY EXISTING. You can walk right into an Apple store today and buy it, but it will still cost you $199.



It will be interesting to follow the success of Lifx and other DIY Kickstarter LED-based projects. There's definitely room for innovation in lighting, but when it comes to consumer products it will be hard to compete with the big boys and their big budget R&D, design, production, and intellectual property lawyers.

Tuesday, November 13, 2012

Lasers & cats

"There are two things that everyone loves: cats and lasers."


That is all. Because I'm too busy write anything else.

Saturday, November 3, 2012

Postdoctoral purgatory

Like most academics, my life is usually summed up in a PHD comic.  Like the depression that came after passing my quals, or the roller-coaster of guilt and stress whenever I go on vacation, or when I found it difficult to write my dissertation.  

Lately, I identify with this one:


Being a postdoc can definitely feel like a gray area, a world between worlds of graduate school and whatever comes after that.

The best part about being a postdoc is my dissertation is DONE. This is HUGE. Many times I find myself paralyzed by anxiety and then realize I'm thinking like a grad student. I have to remind myself, "Relax, you already have your Ph.D." If I don't want to work on a Saturday, for example, I can easily justify staying home because I'm a doctor now and I'm allowed a day off, damnit.

There are other good parts about being a postdoc for sure: larger income, conference travel, having a say in the goings-on of our research center, and mentoring and training younger grad students. All these extra responsibilities, although I enjoy them, can become demanding of my time. To put it lightly. How do full-on profs handle all this stuff? 

Yet there are bad parts about being a postdoc besides being busy, like the pressure to assume all these new responsibilities AND still be productive in my research project. And to PUBLISH. OH MY GOD. YOU GUYS. WHY HAVEN'T I PUBLISHED YET?

Whenever it gets tough, of course I start asking myself other questions. Big questions, like: What life exists beyond academia? 



Tuesday, October 23, 2012

Applications of light: BRAINS

Grad school forces you to live life in a tiny bubble. You spend all your time constantly swamped with making progress on your research project and trying to publish something (anything) meaningful.  It can be difficult to keep up with much else: eating, sleeping, a social life... not to mention the important things like reading all the notable historical papers in your field and keeping up to date with current publications of your colleagues and competitors. All this makes it downright impossible to stay on top of advances in scientific fields outside your own. Who has the time?

Sometimes being a postdoc doesn't feel all that different. I wrapped-up my PhD earlier this year and despite a full-plate of postdoc responsibilities and a never-ending quest to publish, I'm consciously putting more effort into being engaged in the scientific community at large, including reading more general science publications. Though as a specialist in visible light-emitting devices, the articles that particularly catch my eye are any that describe applications of light.  (Pun intended, haha, sorry.)

I was so excited to learn a new word yesterday: Optogenetics.

photo by John Carnett for Popular Science

Optogenetics, a not-that-new term coined by Karl Deisseroth at Stanford, is a way of using light to precisely stimulate parts of the body.  It's done by embedding certain light-sensitive proteins into tissues or cells, which can activate the cells by exposing it to the correct wavelength of light.

You guys!  They can control a rat's brain with frikkin lasers! This made me spit out my drink and go: "WHAT. THAT'S AWESOME. SCIENCE IS SO COOL."

Watch this great 4 minute video from Nature that describes optogentics in more detail.



So far, optogenetic methods have already been used to make several advances in neurological research. Nature considered it so revolutionary, it was named Method of the Year in 2010.

Recently, Stanford scientists were able to use optogenetics to demonstrate that the hypocretin or orexin, a neuro-transmitter that regulates appetite, arousal, and wakefulness, has a big impact on the sleep to wake transition through the stimulation of neurons in the locus coeruleus, part of the brain that stimulates noradrenaline and is critical for arousal and wakefulness.  Neat!  Read the SciCurious article "Sleeping Beauty: magic or hypocretin?" over at Scientific American for more details. 

Saturday, October 20, 2012

How to dress for a conference like a fashionable lady scientist

Ah, conferences. They can be fantastic opportunities to get out of the lab, showcase your research, as well as meet and interact with your peers, collaborators and possibly arch nemeses. Conferences can also trigger some anxiety and social awkwardness. Still, you want to leave a good impression. You want to look your best AND you want to look like you give a shit.

If you spend any time researching proper attire for these conferences, you'll run into all kinds of unhelpful advice like "Dress for success" or "Dress for the job you want." What does that even mean? What am I supposed to wear?

As a grad student and postdoc I was lucky enough to attend a LOT of conferences. I found the specific dress codes for scientific conferences range depending on size, where and when the conference is held, the field, and even age and academic level.

For men, it's easy.  In my field of academic science & engineering, international conferences  in Europe and Asia are generally more conservative and men dress in business attire, so a full suit is appropriate, especially when presenting a talk. Smaller U.S. conferences are typically business-causal, which for a man can range from dress slacks with dress shirt and dress shoes or even dark denim and a casual button-up shirt. If they work for a government lab, their uniform is khakis and a polo shirt. (I swear those guys all look the same! It's so weird!)

from The Loft

For women, clothing requirements are ambiguous and options seemingly infinite.  And, as much as we hate it, women can still be judged harshly for their looks in a male-dominated scientific community. Even by other women! At the time of putting this post together, attendees of the recent Society for Neuroscience conference caused a minor stir online after accusing fellow female scientists of looking like slutty secretaries or being too unattractive.

I doubt there are many female scientists who go to a conference and intentionally dress sexy for male attention, or intentionally dress on the frumpy side because they're ashamed of their femininity. Maybe they just don't know how their outfit comes across to others. Maybe they said to themselves, "This is what I have, so it is good enough." Or "I'm a scientist. Who cares what I'm wearing?" Truth is, people do care (at least a little bit). And you should too (at least a little bit).

It's not vain to want to look feminine and fashionable. It's more about feeling confident and putting your best foot forward. The bottom line is really, wear what you feel confident and comfortable in.

blouse from The Loft

Yet, as a lady scientist, it can be difficult to know specifically what's appropriate, where to shop, or how to put together versatile outfits. Scientifically-driven women like ourselves may not be up-to-date with the latest trends at all, or even care to be. If you're spending all your time wearing jeans and sneakers in the lab, you may not necessarily have a good stock of dressy outfits to bring to a week-long conference. And if all your labmates and coworkers are guys, they're probably not the ones to go to for fashion advice.


Outfit from The Gap

There's definitely a lot of gray area on what looks good and works and what's inappropriate and doesn't work. Now that I'm in my thirties and a postdoc, I like to use every upcoming conference as an excuse to upgrade my tomboyish college wardrobe. A professional conference is the perfect venue to look like a sophisticated, classy, feminine version of myself. I figure I already stand-out by being female in the first place, why hide it trying to dress like one-of-the-guys?

I learned through observations and some trial-and-error experimentation to find out what works for my body and comfort level. Like a scientist.

Blouse and pencil skirt from J. Crew

I will freely admit: I hate shopping, especially clothes shopping.  But shopping with a purpose and knowing what I'm looking for makes it much easier.

So, to help other lady scientists who are looking for advice on what to wear, I polled a few of my gorgeous yet brilliant lady scientist friends for some tips on choosing appropriate, fashionable outfits for science conferences, which I'm compiling here. What follows is a comprehensive boat-load of unsolicited fashion advice.


My ground rules for dressing like a fashionable lady scientist:
  • Your clothes should be comfortable, look good, and help you feel confident. That is the most important.
  • When in doubt, err on the side of caution and go the more conservative and dressed up route. This is true in life in general, ha.
  • No exposed cleavage.  Seriously.  Not even a little.  Button an extra button of your top and if you have big boobs larger breasts, invest in some heavy-duty bras and tops that fit.  
    • [ Note: I hate to sound like I'm slut-shaming here, which is probably why this has been the most controversial advice from comments over the years. My reason for this rule is this: any time I've worn anything remotely low-cut or show any amount of skin, I notice a few men will stare at my body. It makes me VERY uncomfortable and I really hate it. So I follow this rule in any professional setting. That said, this is all about your personal comfort level. If you feel confident, obviously, go for it.] 
  • Quality over quantity.  Spend more money on high-quality clothes that you can wear over and over.  In many cases you definitely get what you pay for.  
  • Know what fits you! It's so important! Your size can change! I feel like my life changed when I went a size larger than I always wore, even though my weight was the same. 
  • Jewelry and accessories can go a long way. That said, sometimes you end up wearing a lanyard badge around your neck the whole time anyway so extra necklace seems redundant. 
  • Sales clerks are really good at helping with sizing and putting outfits together. If you have no idea what you're doing, go to a nice department store and ask for help with the dressing room attendant.  Some stores (i.e. Nordstrom) even offer free fashion consulting.
  • Solid, neutral colors will always be in style.  These include: black, gray, brown, tan, beige, white, off-white, navy blue, light blue, dark green, dark red. 
  • If you're not sure what colors look good on you, check out this handy guide from Gala Darling.
Chunky sweater and skirt from J. Crew
  • A good length for skirts and dresses are just above the knee or just below.
  • "Trendy" and "stylish" are different things. Shoot for stylish, which to me means more classic, things that won't go out of style in a few years.
  • "Dressy" and "sexy" are two different things. I'm thinking about when I was an undergrad and the only non-jeans I had were the my fitted "going out" pants that were not necessarily appropriate for a work event.   
  • A few tricks to tone down a questionably too-sexy outfit: 
    • Opaque (dark) tights instead of bare legs.
    • Flats or oxfords instead of heels.
    • Cardigan or blazer over a fitted top or exposed shoulders. 
    • Camisole to wear under transparent shirts or to cover potential cleavage. 
    • Long shirts/sweaters to layer over jeggings/fitted slacks
This belted sheath dress from Nordstrom looks classy as fuck, but you could tone it down with cardigan and flats.
  • Dress appropriately for your age and level of experience.  A more experienced assistant professor who's chairing a session may get away with a sleeveless sheath dress, bare legs and heels (as shown above), but for a younger grad student presenting a poster this look might make her appear overdressed.


Basic pieces for fashionable lady scientists:
  • Pencil skirt or A-line skirt in black, or another neutral color, just above or just below the knee. (shown here from Nordstrom)
  • A great fitting pair of dress slacks. (shown here from Banana Republic) Pant style trends change a lot. These can also be tough to find off-the-rack. Some stores offer tailoring services, ask the salesclerk about getting them professionally hemmed. 

  • Stretch cotton button-up dress shirt in white, or another neutral color. (shown here from Nordstrom)
  • Pretty, feminine blouses: long sleeve, short sleeve, or sleeveless. No need to shy from prints and bright colors. (shown here from Loft)

  • Solid-colored, scoop-neck or draped-neck t-shirts for wearing alone or layering, also called "shells" - these can be casual or dressy.  (This Halogen top from Nordstrom, below, is the shit. I have it in three colors!)
  • Sheath dress - for a sophisticated nighttime banquet look.  (shown here from Nordstrom)
  • Fitted, dark denim jeans - can be business casual or casual depending on the rest of your outfit. (shown here from Banana Republic)
  • Cardigans. Lots of cardigans. Cardigans in all shapes and colors. Great for layering and cold conference rooms. (shown here from Banana Republic)

  • Blazer. A good cropped blazer will immediately upgrade any outfit, including jeans and a t-shirt, or can be worn with dress slacks for a more formal look.  (shown here from Macy's)
  • Scarf. Keeps you warm on planes AND dresses up an otherwise boring casual outfit AND looks classy as fuck.  If you don't know how to tie a scarf, check out this video.  (shown here from Nordstrom)

  • A full-coverage bra that FITS, preferably one that matches your skin tone.  I'm talking a heavy duty, fully-lined kind that your partner thinks is really ugly but looks good under any outfit. Also keep in mind your bra size changes as you age, so it's a good idea to get refitted if yours are not totally comfortable. (shown here from Macy's)
  • Camisoles a.k.a. camis in neutral tones to wear under semi-transparent or low-cut shirts. (shown here from Macy's). I wear these things all the time! I have them in white, black and nude. Sometimes a silky undershirt like this helps even a simple a t-shirt lay better.  

  • Opaque tights, in black or another neutral color, to wear under skirts or dresses. Are especially helpful for making short skirt seem more conservative. (shown here from Macy's)
  • Faux-leather tote-bag.  I bought a Nine West tote bag for a conference and I loved it so much that it became my default purse and carry-on.  It has pockets for my phone and wallet, fits my laptop, and the best part is I got it at Ross. (shown here from Macy's)

  • A good belt or two or four.  Waist-level to wear over shirts/dresses or to wear with slacks.  Here are some great tips for accessorizing with belts from The New Professional.
  • Jewelry.  A tasteful long necklace, bracelet, or pair of droop earrings can help pull a look together. I've heard some people say "no hoop earrings," as a rule, but I've worn them before at a conferences.
  • Comfortable flats. I love ballet flats. They are so versatile. Get them in a few colors. (shown here from Nordstrom)
  • Comfortable pumps.  Yes, they exist, but you'll need to pay more for ones that are comfortable.  Try to stick to less than 3", avoid stilettos and platforms. (shown here from Aldo Shoes)
  • Oxfords.  My favorite kind of shoe! I like to wear little invisible booty socks underneath and pair them with a cropped dress pants, it's so cute. (shown here from Aldo Shoes)
  • Boots? Stick to calf-length or lower and wear them with longer skirts and/or opaque tights. Boots are hard to pack but so necessary if it's cold and wet outside. If they're impossible to pack, wear them on the plane. If the weather is disgusting at the conference location, you could even wear boots TO the conference and change into flats when you get there. (shown here from Frye on Zappos)



Balancing a look:
Here are some examples of well-balanced outfits (more on Pinterest).

Balance a colorful, feminine blouse with conservative flat-front slacks and thin belt.
from Banana Republic
Dress-up a pair of jeans with a blouse, jewelry and cardigan or blazer.
from Loft
Dark tights and a cardigan will tone-down the sexy-secretary level of a fitted skirt, heels and blouse.
from Nordstrom
Cropped slacks and a tweed blazer with a knit tank underneath.  It's not a pantsuit because they don't match, OK?  This look is so versatile.  She could wear jeans instead for more casual look, wear a button-up blouse instead for more conservative look, or remove the blazer and add jewelry for more sophisticated look.
from Nordstrom

Slim-down a pair of wide leg trousers with a tailored, fitted top and wide belt (at the waist)
Good rule of thumb: baggy on bottom, fitted on top, but not both.
from Donna Karan via Net-a-porter

Wear a loose-fitting blouse and cardigan over trendy skinny-fit slacks (covers the butt).
Good rule of thumb: fitted on bottom, baggy on top, but not both.
The heels the model is wearing look a bit too trendy and impractical for a conference, but a pair of oxfords would be a great alternative.
from Nordstrom

Add some personality to a fitted pencil-skirt and blouse with a hot pink sweater.  I love this look. Doesn't she look so excited to tell you about her poster on organic chemistry research?  Sidenote: the socks + heels thing is trendy right now and I don't really get it haha
from Nordstrom


Pair baggy, masculine trousers with a skinny belt and a pretty, feminine secretary blouse.
This look from The Classy Cubicle.

Dark colors always look very fashionable. I love to experiment with layering.
Also, I'm kind of obsessed with every outfit this girl puts together.
from HipsterHijabis



Other tips for conference travel (what I do):
  • Before you travel, try on every outfit combination at home before you decide what to pack. Try your tops on with the bra you're bringing. Preferably do this when you still have a few extra days to go shopping. You may discover those dress slacks you had in the back of your closet for three years no longer fit. 
  • Pack groups of clothes that are in a similar color family, so most pieces match and are interchangeable. For example, I pack clothes that are all black, gray and blue. This way it's easier to create outfits with different combinations.
  • Pack extra tops and underthings in case you need to change partway through the day, especially if it's warm or you plan to do sightseeing or socializing after the conference.  
  • Make sure you're able to stand and walk comfortably in your shoes.  
  • Bring comfortable shoes.
  • Pack band-aids in case your otherwise comfortable dress shoes rub the back of your heels raw.
  • When you get to the conference, unpack immediately and iron and hang your clothes.
  • Dress in layers.  Always have a cardigan on hand in case the venue's AC is rocking.
  • Umbrella..? Check the weather ahead of time.
  • Observe! Make notes! What are other women wearing? What looks do you like? Make a mental shopping list for next time. :) 
  • Seriously, bring comfortable shoes.

Good stores to shop in: In case you hate shopping like I do and need more inspiration. Check out the 'work clothing' or 'career wear' or 'business wear' sections.


Check out my Pinterest board for all these looks and more.