Nonreciprocal electrical transport phenomena in Rashba system

Nonreciprocal response is a consequence of the inversion symmetry breaking where lots of physical responses have directivity. This is essentially a non-linear response like a circular dichroism and second harmonic generation in non-linear optics. The electrical resistivity, which is the most fundamental physical property of materials, also shows the nonreciprocity; the resistivity depends on the direction of the current. In this study, we have investigated the nonreciprocal electrical transport in polar semiconductor BiTeBr which has simple Rashba-type band structure. The measured nonreciprocity for this material is quantitatively reproduced by simple model; single relaxation time Boltzmann equation for Rashba Hamiltonian with in-plane Zeeman field. In this presentation, we explain mainly about the theoretical model and the analysis of the nonreciprocal electrical transport.