The thermal conductivity of metals in high magnetic fields at low temperatures

Abstract

In heat conductivity measurements between 2 and 4·5° K twenty-seven pure metals have been subjected to a magnetic field of 4 kOe. Of these, Cd, Sn, Pb, Zn, Ga, Ag, Tl and In show appreciable magneto-resistance effects. Single crystals of Cd, Sn and Pb were investigated and of Zn and Ga, single crystals of different orientations. Ag, Tl and In were polycrystalline specimens. Transverse and longitudinal fields were applied, the effect being always greater in the transverse case. Single crystals of Zn, Sn, Cd and a specimen of Tl were investigated in transverse fields up to 18·5 kOe. The thermal resistance of the cadmium crystal was increased by a factor of 1000 at 2·3° K, and the use of this effect in a thermal switch has been suggested. In transverse fields the thermal resistance of all metals was found to rise linearly except for very small fields. Indications of saturation effects were only obtained in longitudinal fields. The results have been discussed on the basis of existing theory.