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arXiv · 1611.05781

Geometric Resonance of Composite Fermions near Bilayer Quantum Hall States

M. A. Mueed·D. Kamburov·L. N. Pfeiffer·K. W. West·K. W. Baldwin·M. Shayegan
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Abstract

Via the application of parallel magnetic field, we induce a single-layer to bilayer transition in two-dimensional electron systems confined to wide GaAs quantum wells, and study the geometric resonance of composite fermions (CFs) with a periodic density modulation in our samples. The measurements reveal that CFs exist close to bilayer quantum Hall states, formed at Landau level filling factors $ν=1$ and 1/2. Near $ν=1$, the geometric resonance features are consistent with half the total electron density in the bilayer system, implying that CFs prefer to stay in separate layers and exhibit a two-component behavior. In contrast, close to $ν=1/2$, CFs appear single-layer-like (single-component) as their resonance features correspond to the total density.

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M. A. Mueed, D. Kamburov, L. N. Pfeiffer, K. W. West, K. W. Baldwin, M. Shayegan. 2016-11-17. Geometric Resonance of Composite Fermions near Bilayer Quantum Hall States. https://doi.org/10.1103/physrevlett.117.246801

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