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Spin Polarization at Semiconductor Point Contacts in Absence of Magnetic Field

Mikio Eto·Tetsuya Hayashi·Yuji Kurotani
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Abstract

Semiconductor point contacts can be a useful tool for producing spin-polarized currents in the presence of spin-orbit (SO) interaction. Neither magnetic fields nor magnetic materials are required. By numerical studies, we show that (i) the conductance is quantized in units of 2e^2/h unless the SO interaction is too strong, (ii) the current is spin-polarized in the transverse direction, and (iii) a spin polarization of more than 50% can be realized with experimentally accessible values of the SO interaction strength. The spin-polarization ratio is determined by the adiabaticity of the transition between subbands of different spins during the transport through the point contacts.

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Mikio Eto, Tetsuya Hayashi, Yuji Kurotani. 2005-07-23. Spin Polarization at Semiconductor Point Contacts in Absence of Magnetic Field. https://doi.org/10.1143/jpsj.74.1934

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