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arXiv · 1604.04943

Observation of anti-levitation of Landau levels in vanishing magnetic fields

W. Pan·K. W. Baldwin·K. W. West·L. N. Pfeiffer·D. C. Tsui
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Abstract

We report an anti-levitation behavior of Landau levels in vanishing magnetic fields in a high quality hetero-junction insulated-gated field-effect transistor. We found, in the Landau fan diagram of electron density versus magnetic field, the positions of the magneto-resistance minima at Landau level fillings \nu=4, 5, 6 move below the 'traditional' Landau level line to lower electron densities. Moreover, the even and odd filling factors show quantitatively different behaviors in anti-levitation, suggesting that the exchange interactions may be important.

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W. Pan, K. W. Baldwin, K. W. West, L. N. Pfeiffer, D. C. Tsui. 2016-04-18. Observation of anti-levitation of Landau levels in vanishing magnetic fields. https://doi.org/10.1103/physrevb.94.161303

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