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Dephasing Time of Two-Dimensional Holes in GaAs Open Quantum Dots

S. Faniel·B. Hackens·A. Vlad·L. Moldovan·C. Gustin·B. Habib·S. Melinte·M. Shayegan·V. Bayot
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Abstract

We report magnetotransport measurements of two-dimensional holes in open quantum dots, patterned either as a single-dot or an array of dots, on a GaAs quantum well. For temperatures $T$ below 500 mK, we observe signatures of coherent transport, namely, conductance fluctuations and weak antilocalization. From these effects, the hole dephasing time $τ_ϕ$ is extracted using the random matrix theory. While $τ_ϕ$ shows a $T$-dependence that lies between $T^{-1}$ and $T^{-2}$, similar to that reported for electrons, its value is found to be approximately one order of magnitude smaller.

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S. Faniel, B. Hackens, A. Vlad, L. Moldovan, C. Gustin, B. Habib, S. Melinte, M. Shayegan, V. Bayot. 2006-09-26. Dephasing Time of Two-Dimensional Holes in GaAs Open Quantum Dots. https://arxiv.org/abs/cond-mat/0609664

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