Increasing the transition temperature greatly decreases the power input to the refrigerator. At liquid nitrogen temperatures (77 degrees Kelvin) the electric power input is only about 20 watts per watt of thermal heat leak. There thus is a strong incentive to develop superconductors with high transition temperatures. Such superconductors, termed high temperature superconductors (HTS), are undergoing intensive development, but have not yet achieved the performance necessary for commercial maglev application.

Low temperature superconductors (LTS) that operate at liquid helium temperatures, or somewhat above, have been developed into well defined commercial products and widely applied. In particular, niobium titanium (NbTi) conductor has been very widely used for decades because of its low cost, high current density, substantial magnetic field capability, and ductility.

The temperature, current density, and magnetic field capability of NbTi and other superconductors are interrelated. As the value of one parameter increases, the value of the others decreases, forming a 3 dimensional inter-relationship. Using these 3-D curves, it is easy to appreciate the immensely strong magnetic fields of commercially available superconductors NbTi and Nb3Sn at liquid helium temperatures.

The M-2000 uses a commercially manufactured NbTi superconductor, similar to that used in the M-2000 Maglev magnets. The ultra-fine filaments of NbTi alloy, each a few microns in diameter, are imbedded in a matrix of high electrical conductivity copper. The overall diameter of the composite NbTi/copper superconducting wire is typically about 1 millimeter. The wire is then wound into an appropriate configuration to form the Maglev magnet, much as ordinary copper wire is wound into the everyday electrical motors and other electrical equipment we use in our homes and work places.