Band-edge properties of a semiconductor alloy: An NMR study of Hg1-xCdxTe.
نویسندگان
چکیده
We report ' Hg NMR measurements of narrow-gap Hg& Cd„Te alloys in the range x =0.20—0.28. By studying temperature dependences, we have identified intrinsic Knight shifts in these alloys. This provides a measure of Hg orbital contributions to conduction-electron states, and we find a consistently strong average contribution from Hg s orbitals. Furthermore, we identify local variations in the Knight shift with spatial variations in conduction-electron densities and symmetries. These characteristics have been related to randomly populated sites within the alloys. We also discuss ' Hg chemical shifts and their relation to local orbital charges.
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عنوان ژورنال:
- Physical review. B, Condensed matter
دوره 48 12 شماره
صفحات -
تاریخ انتشار 1993