Dielectic refrigerator using orientable defect dipoles

Abstract

Abstract This disclosure describes a dielectric refrigerator using orientable defect dipoles and operating between a high temperature, T h reservoir illustratively supplied by a Stirling cycle refrigerator (8° K ≦ T h ≦ 20° K) and a low temperature, T 1 , load, illustratively the liquid He cooling fluid for Josephson junction or other superconducting devices (2° K ≦ T 1 ≦ 6° K). Exemplary practice of this invention provides cooling from the limit of a refrigerator based on the Stirling thermodynamic cycle (20 to 8° K) to operating temperatures of common and useful superconductive devices (3 to 6° K). Orientable electric dipoles of defects in electrically insulating materials, e.g., crystals, are utilized to provide cooling in the range from (8-20 K) to (2-6° K). The following are particular considerations concerning the practice of this invention: use of LiF, MgO and BeO as host crystals; use of OH and/or NH 2 as defects in LiF, and use of HF, HCl, HBr and/or NH as defects in MgO or BeO; mechanical or electromechanical means to make and break thermal contact between dielectric crystal and load and between load and reservoir; and use of thermal rectifiers to obviate the need for thermal switches in order to transfer heat from the load to the refrigerator material and thence to the reservoir.

Inventors

• 👤 James A. Van Vechten

Bibliographic Details