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arXiv · 1606.04221

Individual Cr atom in a semiconductor quantum dot: optical addressability and spin-strain coupling

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

We demonstrate the optical addressability of the spin of an individual Chromium atom (Cr) embedded in a semiconductor quantum dot. The emission of Cr-doped quantum dots and their evolution in magnetic field reveal a large magnetic anisotropy of the Cr spin induced by local strain. This results in the zero field splitting of the 0, +-1 and +-2 Cr spin states and in a thermalization on the magnetic ground states 0 and +-1. The observed strong spin to strain coupling of Cr is of particular interest for the development of hybrid spin-mechanical devices where coherent mechanical driving of an individual spin in an oscillator is needed. The magneto-optical properties of Cr-doped quantum dots are modelled by a spin Hamiltonian including the sensitivity of the Cr spin to the strain and the influence of the quantum dot symmetry on the carrier-Cr spin coupling.

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A. Lafuente-Sampietro, H. Utsumi, H. Boukari, S. Kuroda, L. Besombes. 2016-06-14. Individual Cr atom in a semiconductor quantum dot: optical addressability and spin-strain coupling. https://doi.org/10.1103/physrevb.93.161301

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