Designing quantum dots for solotronics

TL;DR

This paper demonstrates that single magnetic ions in quantum dots can be optically controlled with minimal non-radiative losses, advancing solotronics and enabling potential spin memory applications.

Contribution

It provides experimental evidence that non-radiative recombination is negligible in certain quantum dots with single magnetic ions, expanding the possibilities for solotronics.

Findings

Negligible non-radiative recombination in CdTe:Co and CdSe:Mn quantum dots.

Identification of optimal magnetic ion-quantum dot systems for spin memory.

Experimental validation of optical control of single-ion spins in zero-dimensional structures.

Abstract

Solotronics, optoelectronics based on solitary dopants, is an emerging field of research and technology reaching the ultimate limit of miniaturization. It aims at exploiting quantum properties of individual ions or defects embedded in a semiconductor matrix. As already shown, optical control of a spin of a magnetic ion is feasible employing photo-generated carriers confined in a quantum dot. A non-radiative recombination, regarded as a severe problem, limited development of quantum dots with magnetic ions. Our photoluminescence studies on, so far unexplored, individual CdTe dots with single cobalt ions and individual CdSe dots with single manganese ions show, however, that even if energetically allowed, the single ion related non-radiative recombination is negligible in such zero-dimensional structures. This opens solotronics for a wide range of even not yet considered systems. Basing on the results of our single spin relaxation experiments and on the material trends, we identify optimal magnetic ion-quantum dot systems for implementation of a single-ion based spin memory.