Rashba Spin-Orbit Interaction in Low and High Magnetic Fields (English shop)

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In this work, the Rashba spin–orbit interaction in two-dimensional electron gases (2DEG) of III-V narrow-gap semiconductors is investigated. In these semiconductors, the main cause of spin–orbit interaction is structural inversion asymmetry, whose strength is described by the Rashba parameter a. Both the potential gradients perpendicular to the 2DEG and the interfaces contribute to a. In this work, three measurement methods are used to determine a: Shubnikov–de Haas (SdH) oscillations in strong external magnetic fields, as well as weak antilocalization (WAL) and Al’tshuler–Aronov–Spivak (AAS) oscillations in small external magnetic fields. The strength of a is controlled by applying gate voltages. Measurements on inversion layers of p-type InAs single crystals as well as on InAs/In0.75Ga0.25As heterostructures show SdH oscillations and WAL.