Like a lot of physics departments, we offer an upper-level lab class, aimed at juniors and seniors. There are a lot of ways to approach this sort of course, but one sensible way to think about it is in terms of giving students essential skills and experiences. That is, i’s a course in which they learn to do the things that no physics major should graduate without doing.
I’m sure that other disciplines do something similar, so I thought I might throw this out there as a general question:
What are the essential skills and experiences a student ought to have before graduating with a degree in your discipline?
If you’re a computational theorist, for example, you might say that no student should get a degree without debugging Fortran code. An organic chemist might say that no student should graduate without taking an interpreting an NMR spectrum. A biochemist might want graduating seniors to know how to run a gel and decipher the resulting blobby pictures.
So what are the essential experiences a student in your discipline needs to have?
I come at this from Atomic, Molecular, and Optical (AMO), so my answers involve lasers and atoms. There are two things I think students need to see at least once, and not coincidentally I try to hit both of them with the lab I do in the upper-level course.
One is interferometry. Many of the most precise measurements we make in physics are made possible by the interference of light. Whatever effect you’re studying, if you can find a way to make it cause a slight delay in the propagation of light, you can measure it interferometrically, to ridiculous precision. Michelson interferometers, Mach-Zehnder interferometers, Fabry-Perot interferometers– these are essential tools in physics, and every student should do at least one precision measurement using interferometry.
The other is precision spectroscopy. This doesn’t necessarily mean using a big grating spectrometer to measure line positions, though that’s fine, too. But one of the very coolest things about modern AMO physics is that laser spectroscopy makes the measurement of part-per-billion shifts and effects almost effortless. If you have a halfway decent diode laser, you can measure the hyperfine splitting of rubidium to within a few tens of megahertz, considerably less than a millionth of the frequency of the laser itself. People who do this sort of thing professionally make lasers that are stable to the part-per-trillion level, or even better.
I try to hit both of these in my module of the upper-level lab by having the students first calibrate a Fabry-Perot interferometer, and then use it as a frequency reference to measure the rubidium hyperfine splitting with a scanning diode laser. If they’re careful, they can get the ground-state splitting with an uncertainty of 20-ish megahertz (out of 6800), which is pretty respectable.
(This, by the way, is one of the reasons why I’m unhappy wth 30% error in labs…)
If I could figure out a way to incorporate op-amp based feedback circuits into the lab (having them lock a laser to a frequency reference, say), I’d do that, too. Nobody should be able to market themselves as an experimental physicist without making at least one lock circuit from scratch. I can’t quite work that in, though, so I stick with those two.
So, what do you regard as essential skills and experiences for majors in your field?