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Composite Fermions in Modulated Structures: Transport and Surface Acoustic Waves

Felix von Oppen·Ady Stern·Bertrand I. Halperin
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Abstract

Motivated by a recent experiment of Willett et al. [Phys. Rev. Lett. 78, 4478 (1997)], we employ semiclassical composite-fermion theory to study the effect of a periodic density modulation on a quantum Hall system near Landau level filling factor nu=1/2. We show that even a weak density modulation leads to dramatic changes in surface-acoustic-wave (SAW) propagation, and propose an explanation for several key features of the experimental observations. We predict that properly arranged dc transport measurements would show a structure similar to that seen in SAW measurements.

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Felix von Oppen, Ady Stern, Bertrand I. Halperin. 1998-05-13. Composite Fermions in Modulated Structures: Transport and Surface Acoustic Waves. https://doi.org/10.1103/physrevlett.80.4494

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