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NMR Probing Spin Excitations in the Ring-Like Structure of a Two-Subband System

X. C. Zhang·G. Scott·H. W. Jiang
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Abstract

Resistively detected nuclear magnetic resonance (NMR) is observed inside the ring-like structure, with a quantized Hall conductance of 6e^2/h, in the phase diagram of a two subband electron system. The NMR signal persists up to 400 mK and is absent in other states with the same quantized Hall conductance. The nuclear spin-lattice relaxation time, T1, is found to decrease rapidly towards the ring center. These observations are consistent with the assertion of the ring-like region being a ferromagnetic state that is accompanied by collective spin excitations.

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X. C. Zhang, G. Scott, H. W. Jiang. 2006-10-25. NMR Probing Spin Excitations in the Ring-Like Structure of a Two-Subband System. https://doi.org/10.1103/physrevlett.98.246802

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