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arXiv · cond-mat/0604118

Valley Polarization in Si(100) at Zero Magnetic Field

K. Takashina·Y. Ono·A. Fujiwara·Y. Takahashi·Y. Hirayama
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Abstract

The valley splitting, which lifts the degeneracy of the lowest two valley states in a SiO$_2$/(100)Si/SiO$_2$ quantum well is examined through transport measurements. We demonstrate that the valley splitting can be observed directly as a step in the conductance defining a boundary between valley-unpolarized and polarized regions. This persists to well above liquid helium temperature and shows no dependence on magnetic field, indicating that single-particle valley splitting and valley-polarization exist in (100) silicon even at zero magnetic field.

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K. Takashina, Y. Ono, A. Fujiwara, Y. Takahashi, Y. Hirayama. 2006-06-02. Valley Polarization in Si(100) at Zero Magnetic Field. https://doi.org/10.1103/physrevlett.96.236801

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