Sometimes the view under an electron microscope can be positively scary. I’ll be scrolling along at low magnification, checking out some nanoscale features, when all of a sudden a colossus will loom huge above the nanolandscape. Sometimes I actually jump. Usually it’s a tiny microscopic speck of dust, shaped like a mountain or a monster or a sail. This is one of the largest I’ve seen, maybe a clothing fiber or a carpet fiber - it’s maybe 1/5 the thickness of a single hair. Fortunately, this monster’s presence wasn’t a problem, since I was only testing an etching recipe.
The long valley, surrounded by jagged mountains, occupied by a picturesque leaning castle…. Actually, this is a closeup of a minuscule scratch in a coating of photoresist. At this magnification (2096x), it’s clear that the photoresist has a rough, mountainous surface, caused by the high-energy plasma I’d bombarded it with earlier. The scratch reveals the pale semiconductor below, which was protected everywhere else by the photoresist… here, I can tell that the scratch probably happened after the plasma bombardment, or the semiconductor would be dramatically eaten away.
For a sense of scale, the width of the scratch is about 1/50 the width of a single human hair. A single bacterium could just about fit in the valley sideways.
ThorLabs displays a keen understanding of graduate school - as of a few years ago, they’ve included snack boxes with many of their orders of optics components. The boxes include things like trail mix, granola bars, goldfish crackers, and fruit snacks - not, of course, that this influences any of us grad students in our optomechanics purchasing decisions. I will note, however, that at least one other optomechanics company, Newport, has begun sending snack boxes as well.
A blog reader recently asked me for the names of a few suppliers of laser lab components. A few I’ve used, in approximate order of frequency:
- Edmund Optics
- OZ Optics
- CVI Melles-Griot
And then there are others who specialize in specific types of components, like lasers or filters or precision stages. But the above will get you set up with all the fun LEGO-like parts needed for mounting mirrors and lenses, and steering laser beams around. Or you could build them out of actual LEGOs.
Light in a circular cavity makes a variety of standing wave patterns, some of which look like flowers, wagon wheels, or even tie-fighter spaceships. These images are from my simulations of the light in the cavities of nanolasers - each pattern is called a mode, and the smaller the laser, the simpler the mode tends to be.
In our lasers, the modes that tend to do the best are the whispering gallery modes - for example, the rightmost mode on the second row. Whispering gallery modes get their name from the whispering gallery phenomenon first noticed with sound waves in cathedral domes. People noticed that if they stood along the perimeter of some cathedral domes, the sound waves from a whisper would bounce along the walls of the dome, and could be clearly heard at certain other places along the dome’s perimeter. Whispering gallery modes appear not just for light and sound, but for other kinds of waves as well, like matter waves and gravitational waves.
Q:Someone recently asked me if there were other grad students/scientists blogging pictures from their daily life in the lab. I realized that I only know of a couple scientist bloggers who focus on original content, generated by their own experiences in the lab/field. Do you know of any others, or even of a list somewhere?
Huh. You know, I don’t actually know of that many bloggers off the top of my head that blog about their own science and their own daily life in the lab and field. I mean, I know plenty of them exist, and I’ve come across their work from time to time (on Tumblr and beyond), but few of them have really stuck with me.
I think many (but not all) of us who start writing while we are doing science have a tendency to write about things that may be in our field, but are not what we work on, because we spend enough damn time thinking about our work as it is! That might be my personal bias from grad school coming through, though.
But I also think that scientists writing about their own work, whether they are tenured profs or first-year grad students, is enormously important, both for communicating science in general and communicating the science that you are doing. Because if you don’t talk about it, maybe no one will? Or worse, they may talk about your science in a way you don’t like.
Maybe we can crowdsource a list of grad students and young scientists who blog their own work? Leave yours in a reblog, reply, or comment!
Here’s just a few I know of to get the ball rolling:
- Danielle Lee - The Urban Scientist (she was recently recognized by the White House for her outreach!)
- Christina Agapakis - Oscillator (synthetic biology)
- The Southern Fried Science team writes about their own marine biology research alongside big ocean news
- Christie Wilcox also pokes around in the ocean and writes about it, always very well.
- Jane Hu writes about cognitive psychology here on the Tumblr
There’s hundreds… likely thousands more out there. What are your favorites?
I post my research, but with a focus on interesting images and phenomena that I encounter along the way, rather than on results. That way, I don’t have to worry about whether I should post unpublished results (or whether there are any results worth posting).
I find that writing about life in the lab helps me rediscover some of the sights I’d otherwise begin to take for granted, like the multicolored laser beams or the weird nanolandscapes.
Here are some other bloggers I know of, who post about daily life in the lab:
- Kristof Hegedus - LabPhoto (photography from an organic chemistry lab)
- Jynne Martin was a 2013 artist in residence in Antarctica, blogging photos showing the daily life of Antarctic researchers
I hope this discussion uncovers more of us out there!
The view inside one of our lab’s titanium sapphire infrared lasers - if you see a view like this, you’re doing something wrong. Specifically, you’re not wearing laser goggles around a 10W laser source (bad), and placing your eyeballs at beam height (very bad, yet done almost instinctively by laser rookies). For this photo, my cell phone bravely went where my eyes dared not go, as I lowered it into danger for this shot.
Although the cavity is filled with the laser’s 830nm infrared light, the iPhone 4’s infrared filters seem to be good enough that it’s not picked up on the camera sensor (which is infrared-sensitive). Instead, what shows up is all the bright green light from another laser that powers the infrared laser. The green laser’s a diode laser and can be powered by electricity, but the titanium sapphire laser (a Coherent Mira 900, for those interested) has to be powered by another laser, a 10W beam focused down on a tiny crystal. The titanium sapphire beam, in turn, powers a third laser, an optical parametric oscillator (OPO) that emits light even deeper into the infrared range. The OPO’s major advantage is that its light is tunable over a huge range of infrared wavelengths - if we could see infrared light, we’d see the OPO beam changing through a rainbow of colors.
Usually the lasers are covered by boxes for safety, so stray light from the laser cavity doesn’t end up in eyeballs. We had the lasers open yesterday for a service call from Coherent’s laser technicians - the OPO laser wasn’t working. Fortunately, the problem turned out to be a simple plumbing issue in the chilling lines. Back to science again!
The beachgoers flee as hulking monsters climb from the dark water…
This is a scanning electron microscope image of some various-sized pillars that appeared on one of my samples during a plasma etching test. They’re made of semiconductor, and the bright plain beneath is silicon. Showing through the dark hole in the silicon is a base layer of smooth glass. None of the semiconductor pillars, little guys or monsters, are supposed to have been there - the plasma was supposed to scour the silicon clean, and instead this scene emerged. Fortunately, the next sample was a lot more drama-free.
We want to create an index of the lady scientists on Tumblr, much like shychemist did for all scientists. (Have we thanked you lately?!) However, it’s a bit more challenging as not all of you announce your gender on your blogs. So, if you identify as a woman/female,* let us know if you want to be included!
Ooh ooh great idea! Sign me up for the list!
Traffic looks like fireworks when viewed through diffraction glasses. You can pick up diffraction glasses for pretty cheap online - they’re popular as a trippy party effect. But you can also think of them as giving you the superpower of spectrometer vision, the ability to tell apart different kinds of white light that normally look identical to human eyes. It’s a minor superpower, to be sure.
But how these glasses work is they’ve got diffraction gratings over each eye, which act like thin flexible prisms to spread out white light into its spectrum of colors. With sunlight, halogen, and incandescent light bulbs, you get the familiar rainbow, one smooth blur of all the colors from red to blue. But with many other kinds of light bulbs, such as the new Xenon high-intensity discharge headlights, you can see that a lot of the colors are missing from the rainbow, leaving dark gaps between the remaining colors.