There are a lot of high-tech tools that are absolutely essential to the functioning of my lab. The diode lasers I use are a couple hundred bucks each, and only available from a handful of companies. I’ve got a couple of digital oscilloscopes that are really impressive instruments, packing a huge amount of signal-processing power into a single smallish box. I have an infrared viewer that I use to see the beam, and the lab is literally just about shut down when a colleague needs to borrow it.
Something that people outside of experimental physics don’t really appreciate, though, is that there are also surprisingly low-tech items that are also absolutely essential to the smooth functioning of a physics lab. For example, Post-It notes.
If you look at the optical tables in my lab, or just about any other laser lab in the world, you’ll find Post-It notes all over the place. You see, cartoons aside, lasers are not visible as they pass through clear air, so you need to put something into the beam in order to see it. And you frequently need to make small adjustments to the position of a beam by making small changes to the tilt of a mirror some distance away from the point you care about.
Post-It notes are the perfect solution for this. The 1″x2″ size are small enough to use in beam tracking on even a crowded optical table (and can be folded over and stuck to themselves to make even smaller tabs for really tight places). They can also be stuck to mirror or lens mounts to provide a surface for tracking the beam position from across the table, and can be un-stuck and re-stuck many times for iterative alignment procedures.
(Old computer punch cards are another surprisingly useful item– there’s a 2″ stack on a drawer in my lab, probably from somebody’s Ph.D. thesis back in the day, and they’re always being pressed into service as screens and beam stops. If you find one with a hole at just the right height, they’re also great for checking back-scatter.)
There are a bunch of other low-tech items whose loss would cripple the lab (3/16″ balldrivers are at the top of the list), but Post-Its are right up there for people who play with lasers. If you look in a laser lab, you’ll probably find a bunch of pads of Post-Its scattered around.
What’s your favorite low-tech research essential?