Galvanomagnetic effects in anisotropic metals

The aim of this article is to present an introductory review of those aspects of the isothermal galvanomagnetic effects in metals (which here means the electrical resistance, magnetoresistance and Hall effect) which are peculiar to the existence of an anisotropic electrical conductivity. This anisotropy may be intrinsic to the solid, such as that arising from a non-cubic crystal structure, or it may be induced by the application of the external magnetic field. Such induced anisotropy can itself be divided into two classes : that arising directly from the effect of the Lorentz force upon the itinerant electrons, and that in which the external field is merely an agent which makes evident on a macroscopic scale an anisotropy which exists microscopically, even in the field-free case. The article traces the usual phenomenological formulation of the galvanomagnetic effects, and then particularizes this to the commonly-encountered experimental situations used to study the consequences of both induced and intrinsic anisotropy. The final section consists of a comprehensive compilation of relevant literature, arranged under the headings for the individual elemental metals and semimetals.