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arXiv · 1406.2387

Spin-Polarization of Composite Fermions and Particle-Hole Symmetry Breaking

Yang Liu·S. Hasdemir·A. Wójs·J. K. Jain·L. N. Pfeiffer·K. W. West·K. W. Baldwin·M. Shayegan
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Abstract

We study the critical spin-polarization energy ($\alpha_{\rm C}$) above which fractional quantum Hall states in two-dimensional electron systems confined to symmetric GaAs quantum wells become fully spin-polarized. We find a significant decrease of $\alpha_{\rm C}$ as we increase the well-width. In systems with comparable electron layer thickness, $\alpha_{\rm C}$ for fractional states near Landau level filling $\nu=3/2$ is about twice larger than those near $\nu=1/2$, suggesting a broken particle-hole symmetry. Theoretical calculations, which incorporate Landau level mixing through an effective three-body interaction, and finite layer thickness, capture certain qualitative features of the experimental results.

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Yang Liu, S. Hasdemir, A. Wójs, J. K. Jain, L. N. Pfeiffer, K. W. West, K. W. Baldwin, M. Shayegan. 2014-06-09. Spin-Polarization of Composite Fermions and Particle-Hole Symmetry Breaking. https://doi.org/10.1103/physrevb.90.085301

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