Magnetoconductivity of Aluminum Computed by the Path-Integral Method

Abstract

The components of the electrical magnetoconductivity and magnetoresistivity tensors of aluminum were calculated by the path-integral method using a nearly-free-electron Fermi surface and a uniform relaxation time. Results are presented for longitudinal and transverse magnetoresistance, the longitudinal–transverse components, and the Hall term. The induced torque calculated from the computed magnetoresistivity components is in excellent agreement with measured anisotropy and field dependence of the induced torque. The torque anisotropy results primarily from the longitudinal magnetoresistance anisotropy which arises from variations with crystal orientation of the mean of the orbitally averaged longitudinal component of carrier velocity. The observed magnetic field dependence of the Hall coefficient is reproduced using a temperature-dependent ratio of the relaxation times for the electron and hole bands. The irreducible even-field Hall terms, which are calculated for field directions in the (112) plane, are discussed. The longitudinal–transverse components of magnetoresistivity can saturate at values as high as 0.16 of the zero-field resistivity, but the effects of the longitudinal–transverse magnetoconductivity on the magnetoresistance and Hall coefficients are small. Reported linear high-field magnetoresistance is discussed.