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Spin polarization and metallic behavior of a silicon two-dimensional electron system

Tohru Okamoto·Mitsuaki Ooya·Kunio Hosoya·Shinji Kawaji
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Abstract

We have studied the magnetic and transport properties of an ultra-low-resistivity two-dimensional electron system in a Si/SiGe quantum well. The spin polarization increases linearly with the in-plane magnetic field and the enhancement of the spin susceptibility is consistent with that in Si-MOS structures. Temperature dependence of resistivity remains metallic even in strong magnetic fields where the spin degree of freedom is frozen out. We also found a magnetoresistance anisotropy with respect to an angle between the current and the in-plane magnetic field.

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Tohru Okamoto, Mitsuaki Ooya, Kunio Hosoya, Shinji Kawaji. 2005-12-02. Spin polarization and metallic behavior of a silicon two-dimensional electron system. https://doi.org/10.1103/physrevb.69.041202

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