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arXiv · 0904.4111

Gate control of low-temperature spin dynamics in two-dimensional hole systems

M. Kugler·T. Andlauer·T. Korn·A. Wagner·S. Fehringer·R. Schulz·M. Kubová·C. Gerl·D. Schuh·W. Wegscheider·P. Vogl·C. Schüller
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Abstract

We have investigated spin and carrier dynamics of resident holes in high-mobility two-dimensional hole systems in GaAs/Al$_{0.3}$Ga$_{0.7}$As single quantum wells at temperatures down to 400 mK. Time-resolved Faraday and Kerr rotation, as well as time-resolved photoluminescence spectroscopy are utilized in our study. We observe long-lived hole spin dynamics that are strongly temperature dependent, indicating that in-plane localization is crucial for hole spin coherence. By applying a gate voltage, we are able to tune the observed hole g factor by more than 50 percent. Calculations of the hole g tensor as a function of the applied bias show excellent agreement with our experimental findings.

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M. Kugler, T. Andlauer, T. Korn, A. Wagner, S. Fehringer, R. Schulz, M. Kubová, C. Gerl, D. Schuh, W. Wegscheider, P. Vogl, C. Schüller. 2009-07-01. Gate control of low-temperature spin dynamics in two-dimensional hole systems. https://arxiv.org/abs/0904.4111

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