Single exciton spectroscopy of semimagnetic quantum dots

TL;DR

This paper investigates how spin-exciton interactions and multi-spin correlations influence photoluminescence in Mn-doped semiconductor nanocrystals, providing a comprehensive theoretical framework that aligns with recent experimental observations.

Contribution

It introduces a numerical diagonalization approach to model spin-exciton interactions in semimagnetic quantum dots, unifying experimental results and theoretical understanding.

Findings

Photoluminescence spectra explained by spin-exciton interactions

Multi-spin correlations impact optical properties

Optically induced ferromagnetism modeled successfully

Abstract

A photo-excited II-VI semiconductor nanocrystal doped with a few Mn spins is considered. The effects of spin-exciton interactions and the resulting multi-spin correlations on the photoluminescence are calculated by numerical diagonalization of the Hamiltonian, including exchange interaction between electrons, holes and Mn spins, as well as spin-orbit interaction. The results provide a unified description of recent experiments of photoluminesnce of dots with one and many Mn atoms as well as optically induced ferromagnetism in semimagnetic nanocrystals.