Halbach Array

Halbach Array: "The late Klaus Halbach of Lawrence Berkeley National Laboratory discovered an interesting permanent magnet configuration that concentrates magnetic flux on one side of the array and cancels it on the other. He originally designed it for focusing the beams of particle accelerators. Lawrence Livermore National Laboratory scientists Post and Ryutov developed the idea into a model Maglev train, the only one so far that uses permanent magnets--it floats over a series of short-circuited coils at only 5 mph or so (the 'Inductrack' system). Maglev trains, motors and generators using circular Halbach arrays have already been patented--the advantages include minimized drag from eddy current effects (drag decreases as speed increases), reduced power consumption (no giant electromagnets needed), reduced exposure of train passengers to high magnetic fields, and other things that we haven't even begin to explore yet.

Our only result from experimentation so far has been a one-sided refrigerator magnet. Though it seems trivial at first, this magnet array seems frighteningly close to a magnetic monopole...it was enough to freak out the entire Wondermagnet.com staff!"