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arXiv · cond-mat/9711144

Negative Electron-electron Drag Between Narrow Quantum Hall Channels

H. C. W. Tso·D. J. W. Geldart·P. Vasilopoulos
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Abstract

Momentum transfer due to Coulomb interaction between two parallel, two-dimensional, narrow, and spatially separated layers, when a current I_{drive} is driven through one layer, is studied in the presence of a perpendicular magnetic field B. The current induced in the drag layer, I_{drag}, is evaluated self-consistently with I_{drive} as a parameter. I_{drag} can be positive or negative depending on the value of the filling factor νof the highest occupied bulk Landau level (LL). For a fully occupied LL, I_{drag} is negative, i.e., it flows opposite to I_{drive}, whereas it is positive for a half-filled LL. When the circuit is opened in the drag layer, a voltage ΔV_{drag} develops in it; it is negative for a half-filled LL and positive for a fully occupied LL. This positive ΔV_{drag}, expressing a negative Coulomb drag, results from energetically favored near-edge inter-LL transitions that occur when the highest occupied bulk LL and the LL just above it become degenerate.

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H. C. W. Tso, D. J. W. Geldart, P. Vasilopoulos. 1997-11-15. Negative Electron-electron Drag Between Narrow Quantum Hall Channels. https://doi.org/10.1103/physrevb.57.6561

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