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Ettingshausen Effect around Landau Level Filling Factor nu=3 Studied by Dynamic Nuclear Polarization

Yosuke Komori·Satoru Sakuma·Tohru Okamoto
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Abstract

Spin current perpendicular to the electric current is investigated around Landau level filling factor $ν=3$ in a GaAs/AlGaAs two-dimensional electron system. Measurements of dynamic nuclear polarization in the vicinity of the edge of a specially designed Hall bar sample indicate that the direction of the spin current with respect to the Hall electric field reverses its polarity at $ν=3$, where the dissipative current carried by holes in the spin up Landau level is replaced with that by electrons in the spin down Landau level.

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Yosuke Komori, Satoru Sakuma, Tohru Okamoto. 2007-10-09. Ettingshausen Effect around Landau Level Filling Factor nu=3 Studied by Dynamic Nuclear Polarization. https://doi.org/10.1103/physrevlett.99.146807

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