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arXiv · 1511.05164

Spinless composite fermions in an ultra-high quality strained Ge quantum well

Q. Shi·M. A. Zudov·C. Morrison·M. Myronov
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Abstract

We report on an observation of a fractional quantum Hall effect in an ultra-high quality two-dimensional hole gas hosted in a strained Ge quantum well. The Hall resistance reveals precisely quantized plateaus and vanishing longitudinal resistance at filling factors $ν= 2/3, 4/3$ and $5/3$. From the temperature dependence around $ν= 3/2$ we obtain the composite fermion mass of $m^\star \approx 0.4\,m_e$, where $m_e$ is the mass of a free electron. Owing to large Zeeman energy, all observed states are spin-polarized and can be described in terms of spinless composite fermions.

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Q. Shi, M. A. Zudov, C. Morrison, M. Myronov. 2015-11-16. Spinless composite fermions in an ultra-high quality strained Ge quantum well. https://doi.org/10.1103/physrevb.91.241303

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