Circuitry for the contactless detection of superconducting transitions.
Complete circuitry is presented for the detection of the superconducting transition in powders, or specimens for which the standard four-point resistance measurement cannot be performed. Specimens are placed within an inductance coil, and the change in the coil reactance is monitored as a function of temperature. The sensitivity is sufficient to detect the superconducting transition in 10(-3) cm(3) of lead, and only four integrated circuit packages are required.
Gualtieri
D M
DM
Corporate Research Center, Allied Chemical Corporation, Morristown, NJ 07960, USA.