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Spontaneous spin polarization in quantum point contacts

L. P. Rokhinson·L. N. Pfeiffer·K. W. West
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Abstract

We use spatial spin separation by a magnetic focusing technique to probe the polarization of quantum point contacts. The point contacts are fabricated from p-type GaAs/AlGaAs heterostructures. A finite polarization is measured in the low-density regime, when the conductance of a point contact is tuned to <2e^2/h. Polarization is stronger in samples with a well defined ``0.7 structure''

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L. P. Rokhinson, L. N. Pfeiffer, K. W. West. 2006-04-05. Spontaneous spin polarization in quantum point contacts. https://doi.org/10.1103/physrevlett.96.156602

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