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arXiv · 1112.0056

Anomalous Suppression of Valley Splittings in Lead Salt Nanocrystals without Inversion Center

A. N. Poddubny·M. O. Nestoklon·S. V. Goupalov
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Abstract

Atomistic sp3d5s* tight-binding theory of PbSe and PbS nanocrystals is developed. It is demonstrated, that the valley splittings of confined electrons and holes strongly and peculiarly depend on the geometry of a nanocrystal. When the nanocrystal lacks a microscopic center of inversion and has T_d symmetry, the splitting is strongly suppressed as compared to the more symmetric nanocrystals with O_h symmetry, having an inversion center.

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A. N. Poddubny, M. O. Nestoklon, S. V. Goupalov. 2011-12-01. Anomalous Suppression of Valley Splittings in Lead Salt Nanocrystals without Inversion Center. https://doi.org/10.1103/physrevb.86.035324

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