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arXiv · 1606.05476

Spin dynamics of an individual Cr atom in a semiconductor quantum dot under optical excitation

A. Lafuente-Sampietro·H. Utsumi·H. Boukari·S. Kuroda·L. Besombes
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Abstract

We studied the spin dynamics of a Cr atom incorporated in a II-VI semiconductor quantum dot using photon correlation techniques. We used recently developed singly Cr-doped CdTe/ZnTe quantum dots (A. Lafuente-Sampietro {\it et al.}, [1]) to access the spin of an individual magnetic atom. Auto-correlation of the photons emitted by the quantum dot under continuous wave optical excitation reveals fluctuations of the localized spin with a timescale in the 10 ns range. Cross-correlation gives quantitative transfer time between Cr spin states. A calculation of the time dependence of the spin levels population in Cr-doped quantum dots shows that the observed spin dynamics is controlled by the exciton-Cr interaction. These measurements also provide a lower bound in the 20 ns range for the intrinsic Cr spin relaxation time.

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A. Lafuente-Sampietro, H. Utsumi, H. Boukari, S. Kuroda, L. Besombes. 2016-06-17. Spin dynamics of an individual Cr atom in a semiconductor quantum dot under optical excitation. https://doi.org/10.1063/1.4959243

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