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arXiv · 1009.6211

Spin Texture in Quantum Point Contacts in the Presence of Lateral Spin Orbit Coupling

J. Wan·M. Cahay·P. Debray·R. S. Newrock
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Abstract

A non-equilibrium Green's function formalism is used to study in detail the ballistic conductance of asymmetrically biased side-gated quantum point contacts (QPCs) in the presence of lateral spin-orbit coupling and electron-electron interaction for a wide range of QPC dimensions and gate bias voltage. Various conductance anomalies are predicted below the first quantized conductance plateau (G0=2e2/h) which occur due to spontaneous spin polarization in the narrowest portion of the QPC. The number of observed conductance anomalies increases with increasing aspect ratio (length/width) of the QPC constriction. These anomalies are fingerprints of spin textures in the narrow portion of the QPC.

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J. Wan, M. Cahay, P. Debray, R. S. Newrock. 2010-09-30. Spin Texture in Quantum Point Contacts in the Presence of Lateral Spin Orbit Coupling. https://arxiv.org/abs/1009.6211

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