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Spin Degree of Freedom in the nu =1 Bilayer Electron System Investigated via Nuclear Spin Relaxation

N. Kumada·K. Muraki·K. Hashimoto·Y. Hirayama
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Abstract

The nuclear-spin-relaxation rate 1/T_1 has been measured in a bilayer electron system at and around total Landau level filling factor nu =1. The measured 1/T_1, which probes electron spin fluctuations, is found to increase gradually from the quantum Hall (QH) state at low fields through a phase transition to the compressible state at high fields. Furthermore, 1/T_1 in the QH state shows a small but noticeable increase away from nu =1. These results demonstrate that, as opposed to common assumption, the electron spin degree of freedom is completely frozen neither in the QH nor compressible states.

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N. Kumada, K. Muraki, K. Hashimoto, Y. Hirayama. 2004-10-20. Spin Degree of Freedom in the nu =1 Bilayer Electron System Investigated via Nuclear Spin Relaxation. https://doi.org/10.1103/physrevlett.94.096802

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