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arXiv · 1401.3912

Pinning modes of high magnetic field Wigner solids with controlled alloy disorder

B. -H. Moon·L. W. Engel·D. C. Tsui·L. N. Pfeiffer·K. W. West
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Abstract

For a series of samples with 2D electron systems in dilute Al_x Ga_{1-x}As, with varying x from 0 to 0.8 %, we survey the pinning mode resonances of Wigner solids at the low Landau filling termination of the fractional quantum Hall effect (FQHE) series. For all x studied, the pinning modes are present with frequencies, f_pk, that are consistent with collective weak pinning. For x>=0.22% we find f_pk vs B exhibits a rapid increase that is not present for x=0. We find the observed f_pk is much smaller than values calculated with a simple Wigner solid model which neglects the effects of the disorder on the charge distribution of a carrier.

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B. -H. Moon, L. W. Engel, D. C. Tsui, L. N. Pfeiffer, K. W. West. 2014-01-16. Pinning modes of high magnetic field Wigner solids with controlled alloy disorder. https://doi.org/10.1103/physrevb.89.075310

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