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arXiv · 1504.08182

Microwave spectroscopic observation of a Wigner solid within the 1/2 fractional quantum Hall effect

A. T. Hatke·Yang Liu·L. W. Engel·L. N. Pfeiffer·K. W. West·K. W. Baldwin·M. Shayegan
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Abstract

The fractional quantum Hall effect (FQHE) states at half integer Landau fillings ($\nu$) have long been of great interest, since they have correlations that differ from those of the fundamental Laughlin states found at odd denominators. At $\nu=1/2$ the FQHE has been observed in wide or double quantum wells, and is ascribed to the two-component Halperin-Laughlin $\Psi_{331}$ state. $\Psi_{331}$ excitations carry charge $\pm e/4$, like the carriers of $\nu=5/2$ states which are of interest in quantum computation. Further, such an excitation (quasiparticle or -hole) of $\Psi_{331}$ has unequal, opposite charge in the top and bottom layers, and hence an up or down dipole moment. Here we report evidence for a Wigner solid (WS) of such dipolar quasiholes from a quantitative study of the microwave spectra of a wide quantum well (WQW) at $\nu$ close to 1/2.

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A. T. Hatke, Yang Liu, L. W. Engel, L. N. Pfeiffer, K. W. West, K. W. Baldwin, M. Shayegan. 2015-04-30. Microwave spectroscopic observation of a Wigner solid within the 1/2 fractional quantum Hall effect. https://doi.org/10.1103/physrevb.95.045417

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