Title :
Concept for a high-resolution thermometer utilizing the temperature dependence of the magnetic penetration depth
Author :
Shirron, P.J. ; DiPirro, M.J.
Author_Institution :
NASA/Goddard Space Flight Center, Greenbelt, MD, USA
fDate :
3/1/1993 12:00:00 AM
Abstract :
A thermometer using the temperature dependence of the magnetic penetration depth in superconductors is described which has the potential for temperature resolution, when using a DC superconducting quantum interference device (SQUID) readout, on the order of 1 pK. One such device has been fabricated and characterized to demonstrate proof of concept. It consists of primary and secondary coils of NbTi wire wound on a copper toroidal core on which a thin ( approximately 15-nm) layer of In (T/sub c/=3.4 K) has been deposited. The temperature dependence of the mutual inductance, M(T), or self-inductance, is used to detect changes in temperature. Measurements of M(T) have been made with an AC excitation of the primary for various frequencies and peak magnetic field strengths. Estimates of ultimate temperature resolution are given.<>
Keywords :
composite superconductors; inductance; penetration depth (superconductivity); superconducting junction devices; superconducting thin films; thermometers; Cu toroidal core; DC SQUID readout; NbTi wire; NbTi-Cu; high-resolution thermometer; magnetic penetration depth; mutual inductance; self-inductance; temperature dependence; thin In layer; ultimate temperature resolution; Magnetic devices; Magnetic field measurement; SQUIDs; Superconducting coils; Superconducting devices; Superconducting epitaxial layers; Superconducting filaments and wires; Superconducting magnets; Temperature dependence; Toroidal magnetic fields;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
