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arXiv · 1302.2540

Composite Fermions with Tunable Fermi Contour Anisotropy

D. Kamburov·Yang Liu·M. Shayegan·L. N. Pfeiffer·K. W. West·K. W. Baldwin
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Abstract

The composite fermion formalism elegantly describes some of the most fascinating behaviours of interacting two-dimensional carriers at low temperatures and in strong perpendicular magnetic fields. In this framework, carriers minimize their energy by attaching two flux quanta and forming new quasi-particles, the so-called composite fermions. Thanks to the flux attachment, when a Landau level is half-filled, the composite fermions feel a vanishing effective magnetic field and possess a Fermi surface with a well-defined Fermi contour. Our measurements in a high-quality two-dimensional hole system confined to a GaAs quantum well demonstrate that a parallel magnetic field can significantly distort the hole-flux composite fermion Fermi contour.

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D. Kamburov, Yang Liu, M. Shayegan, L. N. Pfeiffer, K. W. West, K. W. Baldwin. 2013-02-11. Composite Fermions with Tunable Fermi Contour Anisotropy. https://doi.org/10.1103/physrevlett.110.206801

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