Strain-induced coherent dynamics of coupled carriers and Mn spins in a quantum dot

Alban Lafuente-Sampietro (1) , Hervé Boukari (1) , Lucien Besombes (1)

1 NEEL - NPSC - Nanophysique et Semiconducteurs

We report on the coherent dynamics of the spin of an individual magnetic atom coupled to carriers in a semiconductor quantum dot which has been investigated by resonant photoluminescence of the positively charged exciton (X+). We demonstrate that a positively charged CdTe/ZnTe quantum dot doped with a single Mn atom forms an ensemble of optical systems which can be addressed independently. We show that the spin dynamics of the X+-Mn complex is dominated by the electron-Mn exchange interaction and report on the coherent dynamics of the electron-Mn spin system that is directly observed in the time domain. Quantum beats reflecting the coherent transfer of population between electron-Mn spin states, which are mixed by an anisotropic strain in the plane of the quantum dot, are clearly observed.We finally highlight that this strain-induced coherent coupling is tunable with an external magnetic field.

Domaines: Autre [cond-mat.other]

Alban Lafuente-Sampietro, Hervé Boukari, Lucien Besombes. Strain-induced coherent dynamics of coupled carriers and Mn spins in a quantum dot. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2015, 92 (8), pp.081305(R). ⟨10.1103/PhysRevB.92.081305⟩. ⟨hal-01186058⟩