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arXiv · 1211.3672

Thermoelectric response of fractional quantized Hall and re-entrant insulating states in the N=1 Landau level

W. E. Chickering·J. P. Eisenstein·L. N. Pfeiffer·K. W. West
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Abstract

Detailed measurements of the longitudinal thermopower of two-dimensional electrons in the first excited Landau level are reported. Clear signatures of numerous fractional quantized Hall states, including those at $ν= 5/2$ and 7/3, are observed in the magnetic field and temperature dependence of the thermopower. An abrupt collapse of the thermopower is observed below about $T= 40$ mK at those filling factors where re-entrant insulating electronic states have been observed in conventional resistive transport studies. The thermopower observed at $ν= 5/2$ is discussed in the context of recent theories which incorporate non-abelian quasiparticle exchange statistics.

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W. E. Chickering, J. P. Eisenstein, L. N. Pfeiffer, K. W. West. 2012-11-15. Thermoelectric response of fractional quantized Hall and re-entrant insulating states in the N=1 Landau level. https://doi.org/10.1103/physrevb.87.075302

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