Anomalous spin–orbit coupling in high-density two-dimensional electron gas confined in InGaAs/InAlAs quantum well

• Published in: Solid state communications Vol. 152; no. 12; pp. 1042 - 1046
• Main Authors: Gao, K.H., Lin, T., Wei, L.M., Liu, X.Z., Chen, X., Yu, G., Gu, Y., Zhang, Y.G., Dai, N., Chu, J.H.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.06.2012; Elsevier
• Subjects: A. InGaAs/InAlAs quantum well; Condensed matter: electronic structure, electrical, magnetic, and optical properties; D. Rashba spin splitting; D. Spin–orbit coupling; Electron states and collective excitations in thin films, multilayers, quantum wells, mesoscopic and nanoscale systems; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Physics; Quantum wells; D. Spin–orbit coupling; A. InGaAs/InAlAs quantum well; D. Rashba spin splitting; Rashba effect; Gallium Indium Arsenides Mixed; Electrical conductivity; D. Spin-orbit coupling; Quantum wells; Oscillations; Aluminium Indium Arsenides Mixed; Two-dimensional electron gas; Weak localisation; Spin-orbit interactions; Non linear effect; Magnetoresistance; Shubnikov-de Haas effect
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2012.03.023

We study the magnetotransport property of a high-density two-dimensional electron gas confined in InGaAs/InAlAs quantum well. Both beating pattern in the Shubnikov–de Hass oscillation of resistivity and weak antilocalization effect are observed. From these two effects, Rashba spin-splitting energy is extracted. The extracted Rashba spin-splitting energy shows a nonmonotonic dependence on Fermi wave vector, contrary to the prevailing linear Rashba model. This anomalous behavior can be attributed to the nonlinear Rashba spin-splitting mechanism [Yang et al., Phys. Rev. B 74 (2006) 193314]. ► Both beating pattern and weak antilocalization effect are observed in InGaAs/InAlAs quantum well. ► The extracted Rashba spin-splitting energy shows a nonmonotonic dependence on Fermi wave vector. ► This anomalous spin–orbit coupling can be attributed to the nonlinear Rashba spin-splitting mechanism.