Quantum oscillations and optical conductivity in Rashba spin-splitting BiTeI

Abstract

We report the observation of Shubnikov-de Haas (SdH) oscillations in single crystals of the Rashba spin-splitting compound BiTeI, from both longitudinal (\(R_{xx}(B)\)) and Hall (\(R_{xy}(B)\)) magnetoresistance. Under magnetic field up to 65 T, we resolved unambiguously only one frequency \(F = 284.3\pm 1.3\) T, corresponding to a Fermi momentum \(k_{F} = 0.093\pm 0.002\)\AA\(^{-1}\).The amplitude of oscillations is strongly suppressed by tilting magnetic field, suggesting a highly two-dimensional Fermi surface. Combining with optical spectroscopy, we show that quantum oscillations may be consistent with a bulk conduction band having a Rashba splitting momentum \(k_{R}=0.046\pm\)\AA\(^{-1}\).