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Spectroscopy of Valley Splitting in a Silicon/Silicon-Germanium Two-Dimensional Electron Gas

Srijit Goswami·Mark Friesen·J. L. Truitt·Charles Tahan·L. J. Klein·J. O. Chu·P. M. Mooney·D. W. van der Weide·S. N. Coppersmith·Robert Joynt·M. A. Eriksson
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Abstract

The lifting of the two-fold degeneracy of the conduction valleys in a strained silicon quantum well is critical for spin quantum computing. Here, we obtain an accurate measurement of the splitting of the valley states in the low-field region of interest, using the microwave spectroscopy technique of electron valley resonance (EVR). We compare our results with conventional methods, observing a linear magnetic field dependence of the valley splitting, and a strong low-field suppression, consistent with recent theory. The resonance linewidth shows a marked enhancement above $T\simeq 300$ mK.

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Srijit Goswami, Mark Friesen, J. L. Truitt, Charles Tahan, L. J. Klein, J. O. Chu, P. M. Mooney, D. W. van der Weide, S. N. Coppersmith, Robert Joynt, M. A. Eriksson. 2006-12-18. Spectroscopy of Valley Splitting in a Silicon/Silicon-Germanium Two-Dimensional Electron Gas. https://arxiv.org/abs/cond-mat/0408389

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