Q & A: Inexpensive superconductor

is it posible to make an inexpebsive super conductor myself
- mike (age 16)

Sure, but depending on your choice of superconducting material, the real expense may be in the cryogenics (read: cold temperatures) needed to make your material superconduct. The first superconductor to be discovered was elemental mercury, which isn't all that expensive. The hard part is getting the liquid helium needed to cool it down below its critical temperature. Another common material which superconducts is pure lead. Watch out -- both lead and mercury are poisonous and are therefore hazardous to work with. (Niobium is a more convenient material, used, along with some of its allowys, for the wires of most commercial superconducting magnets.mbw)

You might be able to get some Yttrium Barium Copper Oxide (YBCO) high-Tc superconducting ceramics from scientific supply houses. They are commonly used in lecture demonstrations, and require no more than liquid nitrogen (also easy to come by, probably from the same scientific supply houses). A common demonstration is the levitation of a small permanent magnet above a disk of this stuff in a styrofoam cup with liquid nitrogen in it. Be very careful with liquid nitrogen! It can cause severe damage to your skin if it touches you (and worse if it wets your clothes). It can also displace the oxygen in air, suffocating you if you don't have proper ventilation when using and storing it. (I saw someone carrying a few dewars of liquid nitrogen in the back seat of his car with the windows rolled up. I hope he had the fan on -- this can be a hazard on the road).

Tom

(published on 10/22/2007)