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Studies of the Temperature-Driven Flow Lines and Phase Transitions in a Two-Dimensional Si/SiGe Hole System

C. T. Liang·C. F. Huang·Yu-Ming Cheng·Tsai-Yu Huang·Y. H. Chang·Y. F. Chen
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Abstract

We have performed low-temperature transport experiments on a Si/SiGe hole system. The measured transverse and longitudinal condductivities $σ_{xx}$ and $σ_{xy}$ allow us to study the magnetic-field-induced transitions in the system. In particular, we present the first study of the temperature-driven flow lines in the "anomalous Hall insulator" regime near a Landau level filling factor $ν=1.5$. The "anomalous" temperature-driven flow lines could be due to the unusual energy level scheme in a Si/SiGe hole system. Moreover, for $3<ν<5$, there is a temperature-independent point in $ρ_{xx} (B)$, $ρ_{xy} (B)$, $σ_{xx}$, and $σ_{xy}$ which corresponds to a boundary of the quantum phase transition.

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C. T. Liang, C. F. Huang, Yu-Ming Cheng, Tsai-Yu Huang, Y. H. Chang, Y. F. Chen. 2002-03-23. Studies of the Temperature-Driven Flow Lines and Phase Transitions in a Two-Dimensional Si/SiGe Hole System. https://arxiv.org/abs/cond-mat/0201333

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