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

Alban Lafuente-Sampietro (1) , H. Utsumi (2) , Hervé Boukari (1) , Shinji Kuroda (2) , Lucien Besombes (1)

1 NEEL - NPSC - Nanophysique et Semiconducteurs
2 Université de Tsukuba = University of Tsukuba

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 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 dominated by the exciton-Cr interaction. These measurements also provide a lower bound in the 20 ns range for the intrinsic Cr spin relaxation time.

Mots clés: spin; quantum dot

Domaines: Autre [cond-mat.other]

Alban Lafuente-Sampietro, H. Utsumi, Hervé Boukari, Shinji Kuroda, Lucien Besombes. Spin dynamics of an individual Cr atom in a semiconductor quantum dot under optical excitation. Applied Physics Letters, 2016, 109 (5), pp.053103. ⟨10.1063/1.4959243⟩. ⟨hal-01353359⟩