Charge Conductance of a Metal/Semiconductor/Metal based a Direct Rashba-Dresselhauss Spin Orbit Interaction

Abstract We theoretically study the conductance spectrum of metal/semiconductor/metal junction incorporating direct Rashba–Dresselhaus spin–orbit interaction (RDSOI). The system is modeled using Dirac delta-function potentials to represent interface mismatches. Both single- and double-junction configurations are considered. In the single-junction system, the conductance exhibits a sharp increase near the flat-band energy of the RDSOI region and gradually decreases with increasing bias voltage. This behavior is strongly dependent on the interface transparency, quantified by the barrier strength. While varying the relative strengths of Rashba and Dresselhaus interaction does not qualitatively alter the conductance spectrum, an overall enhancement in spin–orbit interaction reduces the threshold bias voltage. For the double-junction system, quantum interference effects within the RDSOI region give rise to bias-dependent conductance oscillations. The amplitude and frequency of these oscillations are governed by the length of the RDSOI segment and the interface potential. Additionally, increasing the barrier height suppresses conductance and shifts the resonance peaks, reflecting modified tunneling conditions.