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arXiv · 1408.1981

CdSe/ZnSe quantum dot with a single Mn$^{2+}$ ion - a new system for a single spin manipulation

Tomasz Smoleński
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Abstract

We present a magneto-optical study of individual self-assembled CdSe/ZnSe quantum dots doped with single Mn$^{2+}$ ions. Properties of the studied dots are analyzed analogously to more explored system of Mn-doped CdTe/ZnTe dots. Characteristic sixfold splitting of the neutral exciton emission line as well as its evolution in the magnetic field are described using a spin Hamiltonian model. Dynamics of both exciton recombination and Mn$^{2+}$ spin relaxation are extracted from a series of time-resolved experiments. Presence of a single dopant is shown not to affect the average excitonic lifetime measured for a number of nonmagnetic and Mn-doped dots. On the other hand, non-resonant pumping is demonstrated to depolarize the Mn$^{2+}$ spin in a quantum dot placed in external magnetic field. This effect is utilized to determine the ion spin relaxation time in the dark.

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Tomasz Smoleński. 2014-08-08. CdSe/ZnSe quantum dot with a single Mn$^{2+}$ ion - a new system for a single spin manipulation. https://doi.org/10.1063/1.4913831

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