Optical Manipulation of a Single Mn Spin in a CdTe-Based Quantum Dot

TLDR

Two coupled CdTe quantum dots, one hosting a single Mn ion, were investigated using continuous‑wave and modulated photoluminescence, photoluminescence excitation, and photon‑correlation techniques. The study demonstrates optical writing of the Mn spin state via spin‑polarized carriers from a neighboring dot, with orientation times of 20–100 ns, storage times extended to hundreds of microseconds under a 1 T magnetic field, and simple rate‑equation models accurately describing the static and dynamic behavior.

Abstract

Two coupled CdTe quantum dots, selected from a self-assembled system, one of them containing a single Mn ion, were studied by continuous wave and modulated photoluminescence, photoluminescence excitation, and photon correlation experiments. Optical writing of information on the spin state of the Mn ion has been demonstrated, using the orientation of the Mn spin by spin-polarized carriers transferred from the neighboring quantum dot. Mn spin orientation time values from 20 to 100 ns were measured, depending on the excitation power. Storage time of the information on the Mn spin was found to be enhanced by application of a static magnetic field of 1 T, reaching hundreds of microseconds in the dark. Simple rate equation models were found to describe correctly the static and dynamical properties of the system.