Chris Ko's photos' photostream

I didn't take this picture, but it is so cool I couldn't resist miming! The original version was here:

www-outreach.phy.cam.ac.uk/physics_at_work/2009/photo_gal...

I was giving talks to groups of secondary school students about research in our group. The physics wasn't that impressive to them, but they enjoyed the demonstrations immensely. We had a maglev train set and they were all wowing at it.

It was a train track made of magnets, and a piece of superconductor cooled with liquid nitrogen. In the superconducting state, the superconductor expels all week magnetic field due to the Meissner effect, and levitates. Part of the slight complications that we always omit in the talks are that when we put the superconductor, we always push it down hard, so that we can force some field lines through it. This is called flux pinning and it is what allows it to follow the track.

Sam is our designer/technician. At 85, he's already retired three times! He is always hardworking and gives you the finest thing with the best design you can dream of. He's supposed to be part-time, but he comes in for 8 to 5, 5 days a week. He is simply adorable.