The Lorenz Number of Single Crystals of Lead and Indium in Transverse Magnetic Fields

Abstract

Since the theoretical work of Lifshitz¹ and his school, and the experimental measurements of Alekseevskii and Gaidukov,¹ the problem of the electrical magnetoresistance is solved in principle and there remains only the task of explaining the experimental results in terms of the topological structure of the Fermi surface. On the other hand, only a few measurements exist on the thermal magnetoresistance² of metals and, apart from the investigations of Grüneisen and co-workers³ and de Nobel⁴ in the liquid-hydrogen range and of Alers⁵ and Wyder⁶ in the liquid-helium range, no simultaneous measurements exist of resistivity and thermal conductivity at high fields in very pure metals where the heat is carried almost entirely by the electrons. Furthermore, most of the work that has been done was carried out on polycrystalline material. There is, however, a certain interest in investigations of this kind.⁷ In this paper, we present preliminary results on the electrical and thermal magnetoresistance of a lead and an indium single crystal.