Lab Stories
drorzel | June 27, 2007It's been ages since I posted a True Lab Story, mostly because I've been too busy to do anything really dumb. I had a good day for True Lab Stories yesterday, though, so here's a tale of something idiotic I did, or, rather, had my students do.
I have a student working on a project to put anti-reflection coatings on some diode lasers, which will help improve their performance in various ways that don't really matter here. This requires the deposition of a very even layer of material that's a couple hundred nanometers thick, which we do using a vacuum evaporator. This consists of a bell jar…
drorzel | February 7, 2007So, what's the deal with last night's silly obituary? Basically, the main laser in my experiment died because I'm a jackass.
More specifically, the laser in question is a diode laser, similar to the kind found in CD and DVD players. These are broadly tunable, available in a wide range of powers and wavelengths, and relatively cheap. They're also extremely sensitive to static shock, to the point where I have to be careful to always touch something metal before working on the laser or anything close to it.
To check that we have successfully tuned the laser to the right wavelength, we need to do…
drorzel | September 7, 2006The story about Bloch oscillation gravity measurements reminds me of a True Lab Story about a different sort of sensitive measurement made using cold atoms, made during my grad school days. Sadly, this one wasn't particularly useful...
The standard technique for accumulating large numbers of cold atoms is a thing called a magneto-optical trap, which uses a combination of laser light and magnetic fields to trap a cloud of atoms and confine them in a small region of space. This works by setting up a magnetic field that goes to zero at a specific point in space, and increases as you move away…
drorzel | August 31, 2006(A couple of regular commenters will recognize this one...)
Every working research lab has a sort of rhythm to it. There's always a collection of background sounds, in a particular pattern, that indicates that the lab is functioning properly. When I was a post-doc, the pattern was something like three mintues of white noise (the humming of the fans on the various electronic instruments, and the cooling water running through the magnet coils), followed by a sharp click (a mechanical shutter closing), then a loud clunking sort of noise (as the high-current supply for the magnetic trap switched…
drorzel | August 17, 2006Back when I was an undergrad, I spent the summer before my senior year on campus working on my thesis project (trying to build a MOT for rubidium, which never did work). That same summer, one of the guys I did problem sets with, we'll call him J., who was only a rising junior, was working with the oldest member of the faculty on a different experimental project.
My summer actually went pretty well, but J. and his advisor had one of those nightmare stretches where absolutely nothing would work right. Something would break, and when they got it fixed, something else would break. It was awful,…
drorzel | August 17, 2006True Lab Stories really are everywhere these days. Via Inside Higher Ed's Around the Web, a blog called "What the Hell Is Wrong With You?" offers True Lab Stories: The Party Game (my name, not hers):
Back in the good old days, when La Blonde Parisienne and I were bright young grad students working in the same genetics lab, we used to play a little game called "Too Stupid To Be A Scientist." The game goes like this: you do something stupid, and you tell the other person what a stupid thing you did, and they cheer you up by telling you something even stupider they did. For example, one day I…
drorzel | August 16, 2006True Lab stories are everywhere, as Arcance Gazebo today features a story of new and interesting liquid nitrogen experiments:
Condensed matter labs such as ours receive frequent deliveries of liquid nitrogen in one- or two-hundred liter dewars. Unfortunately, most of the Berkeley cond-mat labs are in Birge Hall, which has no loading dock, so that the LN2 dewars arrive on the first floor of neighboring LeConte where they must be wheeled over to their destination by some low-seniority student. Since the Berkeley campus is on a hill, the loading dock at the back of the building is one floor…
drorzel | August 14, 2006This isn't the usual story about lab mishaps, but I'm not quite sure what other category to put it in. It is a true story about my lab in grad school, though, so we'll call it a True Lab Story.
The mid-90's was not a great time to be working in a government lab, particularly NIST. I mean, it was better than being out on the street, but funding was kind of tight, and the "Contract With America" Republicans of '94 were making noises about massive spending cuts, and threatening to eliminate the Department of Commerce altogether (mostly because they hated Ron Brown, the first Secretary of…
drorzel | June 9, 2006It's been a while since I did a True Lab Story, and it seems like an appropriate sort of topic for a rainy Friday when I have grades to finish. I'm running out of really good personal anecdotes, but there are still a few left before I have to move entirely to hearsay. And who knows, maybe I'll break something in spectacular fashion between now and then...
Anyway, lab safety offices are a rich source of True Lab Stories. Not just because they have to clean up from the really spectacular disasters, but also because their desire to prevent disasters sometimes leads to inflexible applications of…
drorzel | May 8, 2006A low-key True Lab Story, in honor of the previous post on knowing more about your experiment than anybody else.
One of the first times I had to run my grad school experiment all by myself, I had trouble getting the discharge in the metastable atom source to light. I went through all the usual steps, but nothing worked. Happily, the student who had built the experiment was still around, and working on writing up his thesis, so I went over to his office and told him what the problem was. He said "I'll take a look," and we headed over to the lab.
Before we even got into the room, he started…
drorzel | April 21, 2006I'm still feeling pretty lethargic, but I hope that will improve when I get to lecture about the EPR paradox in Quantum Optics today (it's going to be kind of a short lecture, unless I can ad-lib an introduction to Bell's Theorem at the end of the class, but then I've been holding them late for three weeks already...). In an effort to perk myself up through blogging, here are some amusing tales about mishaps involving electricity.
(First, a disclaimer: Though these stories are presented in a manner that (hopefully) makes them sound amusing, most of what I describe here is, in fact, incredibly…
drorzel | March 27, 2006For technical reasons, it turns out that alkali metal atoms are particularly good candidates for laser cooling. Rubidium is probably the most favorable of all of them-- some atomic physicists jokingly refer to it as "God's atom"-- but all of the alkalis, even Francium, have been cooled and trapped.
Of course, alkali metal elements are also the ones that explode when they come in contact with water. They're insanely reactive, so you have to be very careful handling them. As a result, they're usually shipped either in vacuum-sealed ampoules, or as chunks of metal packed in some oily liquid, to…
drorzel | March 23, 2006(Series explanation here.)
The lab I worked in in grad school contained a bunch of miscellaneous objects whose purpose was a little hard to discern. One of the oddest was a big heavy acrylic lens. It was probably an inch thick, and two or three inches in diameter, and had four screw holes around the outside edge. It wasn't a terribly good lens, but it was a lot better than you would've expected from the origin story.
(More after the cut.)
The experiments we were doing required ultra-high vacuum, despite a fairly high gas load, so we had a variety of big vacuum pumps. One of the pumps we used…
drorzel | March 15, 2006(Series explanation here.)
When I was in grad school, I worked in a lab with an incredibly high density of laser technology. We had not one but two Ti:sapphire systems, with 15 W argon ion lasers pumping Coherent 899 ring lasers, plus a pulsed YAG/ dye laser system, and a couple of miscellaneous diode lasers.
The argon ion lasers drew a great deal of current, and required water cooling to keep them from overheating and suffering major damage. The lab provided circulating water at a regulated temperature (55 F), but wherever they were getting the water from, it had large amounts of clay in it…
drorzel | March 15, 2006Every good blog needs a signature recurring element. Dave and Greta have Casual Fridays, RPM has Double Entendre Fridays, Grrlscientist has Birds in the News, PZ has Say Mean Things About Religious People Days-That-End-In-Y, Orac has EneMan...
I'm not organized enough to commit to posting things in a certain category on a specific day of the week, butlater today (through the miracle of scheduled posting) I'm going to roll out an intermittent series of posts based on True Lab Stories. As the original post says, these are not moral or uplifting tales. They won't necessarily have a coherent…
drorzel | March 9, 2006As a sort of cautionary counterpoint to the anecdote in my How to Tell a True Lab Story post, Derek Lowe has the story of somebody who pulled the same trick with a big commercial liquid nitrogen tank:
The cylinder had been standing at one end of a ~20' x 40' laboratory on the second floor of the chemistry building. It was on a tile covered 4-6" thick concrete floor, directly over a reinforced concrete beam. The explosion blew all of the tile off of the floor for a 5' radius around the tank turning the tile into quarter sized pieces of shrapnel that embedded themselves in the walls and doors…
drorzel | January 27, 2006This is true.
A guy I knew in graduate school, he had a buddy who was working late in the lab one night. He was all alone, and he got a little bored, so he took a two-liter soda bottle, and he filled it halfway up with liquid nitrogen. Then he screwed the cap on tight.
Now, liquid nitrogen, when it boils, it takes up something like 700 times the volume of the liquid. So this guy, he's got this bottle, and he's kicking it around in the hall. But the bottle starts to swell up, so he tries to open the cap, and it's stuck. So he runs into the bathroom, and he dumps it in a sink, and runs back out…