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arXiv · 0907.5396

Breakdown of Particle-Hole Symmetry in the Lowest Landau Level Revealed by Tunneling Spectroscopy

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

Tunneling measurements on 2D electron gases at high magnetic field reveal a qualitative difference between the two spin sublevels of the lowest Landau level. While the tunneling current-voltage characteristic at filling factor $ν= 1/2$ is a single peak shifted from zero bias by a Coulomb pseudogap, the spectrum at $ν=3/2$ shows a well-resolved double peak structure. This difference is present regardless of whether $ν=1/2$ and $ν= 3/2$ occur at the same or different magnetic fields. No analogous effect is seen at $ν= 5/2$ and 7/2 in the first excited Landau level.

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J. P. Eisenstein, L. N. Pfeiffer, K. W. West. 2009-07-30. Breakdown of Particle-Hole Symmetry in the Lowest Landau Level Revealed by Tunneling Spectroscopy. https://doi.org/10.1016/j.ssc.2009.08.004

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