There Are Worse Problems to Have

Next term, I’m slated to offer one of our “Advanced Topics in Physics” upper-level elective classes. I was originally asked to do atomic physics, but looking at the syllabus and available texts, I decided I’d rather take a different tack, and agreed to develop a new course instead.

I call myself an atomic physicist, and I go to the annual meetings of the Division of Atomic, Molecular, and Optical Physics (this year in Knoxville, whee!), but most of what falls under that heading these days is not what old-school guys would call atomic physics– spectroscopy, atomic structure, etc. Most of what you hear about at DAMOP these days is really about using the tools and techniques of atomic physics to do other things. I wanted to teach a class that reflected that.

The course-catalogue description I came up with for what we do is “Quantum Optics,” which I’m using in a slightly more inclusive manner than many people who talk about quantum optics do. The definition I gave is below the fold:

Quantum Optics: The study of the interaction of light and matter in systems where the wave nature of matter and the particle nature of light must be taken into account. Topics may include single-photon interference, correlated photons and the EPR paradox, quantum computing, quantum cryptography and quantum teleportation, atom optics and atom interferometry, laser cooling and Bose-Einstein Condensation, and implications of quantum mechanics for nanomaterials and nanodevices.

(The first “and” should probably be an “or,” but I was in a hurry when I wrote that for the course catalogue…)

That’s an impressive-sounding list of topics, and I won’t come near doing all of them, not in ten weeks of class. The interesting thing here, though, is that it’s actually possible to describe all those things with surprisingly little math. Particularly if you spend a little time introducing the Dirac notation, which buries a lot of the ugly calculus steps, and re-casts a lot of QM as linear algebra.

Of course, the immediate snag here is that there isn’t a good textbook at the undergraduate level that does these things. There’s a general QM book that takes the state-vector approach (sort of an undergrad version of Sakurai), but it doesn’t cover the topics I want. There are plenty of books that do cover the interesting topics, but they mostly do it at a grad-student level, with more heavy math than I want to deal with, or at a pop-science sort of level, with lots and lots of hand-waving.

In the end, I’ve settled on using a fairly chatty undergrad-level book– The Quantum Challenge by Greenstein and Zajonc– that covers a lot of the topics I’m interested in with a sort of “Gosh, QM is weird” slant. It has the occasional integral, but the math is pretty sparse, so the plan is to use it as a readable guide to the concepts, and do the mathematical formalism in class. We’ll see how that works.

That’s one problem. The other problem didn’t show up until pre-registration, which ended Friday. The last time I taught one of these classes (regular physical optics), I ended up having to make personal appeals to a number of students to get the enrollment up to a level where we could actually offer the course (the college requires six students in order to run a class, though you can usually get approval with four and some grovelling). I wound up with eight students, three of them engineering majors taking it as an elective. I figured that was a nice, reasonable number of students as a test bed for a new class. I even agreed to make it a writing-intensive course, because some of our students need that, and it’s a good topic for library research papers.

This year, I’ve got twelve pre-registered, and one guy on term abroad who expressed an interest, but hasn’t signed up yet. That’s without even mentioning it to the engineering departments– they’re all physics majors.

Looks like this is going to be a little more work than I thought…