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arXiv · 1010.1885

Anisotropy of Magnetoresistance Hysteresis around the $ν=2/3$ Quantum Hall State in Tilted Magnetic Field

K. Iwata·M. Morino·A. Fukuda·N. Kumada·Z. F. Ezawa·Y. Hirayama·A. Sawada
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Abstract

We present an anisotropy of the hysteretic transport around the spin transition point at Landau level filling factor $ν=2/3$ in tilted magnetic field. When the direction of the in-plane component of the magnetic field $B_{\parallel}$ is normal to the probe current $I$, a strong hysteretic transport due to the current-induced nuclear spin polarization occurs. When $B_{\parallel}$ is parallel to $I$, on the other hand, the hysteresis almost disappears. We also demonstrate that the nuclear spin-lattice relaxation rate $T_{1}^{-1}$ at the transition point increases with decreasing angle between the directions of $B_{\parallel}$ and $I$. These results suggest that the morphology of electron spin domains around $ν=2/3$ is affected by the current direction.

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K. Iwata, M. Morino, A. Fukuda, N. Kumada, Z. F. Ezawa, Y. Hirayama, A. Sawada. 2010-10-10. Anisotropy of Magnetoresistance Hysteresis around the $ν=2/3$ Quantum Hall State in Tilted Magnetic Field. https://doi.org/10.1143/jpsj.79.123701

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