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We use magneto-resistance measurements to investigate the effect of texturing in polycrystalline bismuth thin films. Electrical current in bismuth films with texturing such that all grains are oriented with the trigonal axis normal to the film plane is found to flow in an isotropic manner. By contrast, bismuth films with no texture such that not all grains have the same crystallographic orientation exhibit anisotropic current flow, giving rise to preferential current flow pathways in each grain depending on its orientation. Extraction of the mobility and the phase coherence length in both types of films indicates that carrier scattering is not responsible for the observed anisotropic conduction. Evidence from control experiments on antimony thin films suggests that the anisotropy is a result of bismuth's large electron effective mass anisotropy. [ABSTRACT FROM AUTHOR]

We have developed a robust analytical methodology for modeling the anisotropic transport distribution function, which can be then used to describe various transport properties of anisotropic systems, including the electrical conductivity, carrier mobility, Seebeck coefficient, and thermal conductivity. Our methodology has considered the general cases for 3-, 2-, and 1-dimensional systems with parabolic, non-parabolic, and linear dispersion relations. Calculations are made using both the relaxation time approximation and the mean free path approximation. We have found that the Onsager relation can be violated under certain conditions. Furthermore, the methodology developed in the present work is compared with the traditionally used numerical methodology. [ABSTRACT FROM AUTHOR]