Spin-Forster transfer in optically excited quantum dots

TL;DR

This paper investigates energy and spin transfer mechanisms in coupled quantum dots, highlighting the roles of resonance, exchange, and spin-orbit interactions, and introduces a new method for calculating F"orster transfer beyond the dipole approximation.

Contribution

It presents a detailed analysis of spin and energy transfer processes in quantum dots and introduces a novel mathematical approach for F"orster transfer calculations beyond the dipole-dipole approximation.

Findings

Transfer rates depend on resonance conditions.

Spin transfer involves exchange and spin-orbit interactions.

A new calculation method for F"orster transfer is proposed.

Abstract

The mechanisms of energy and spin transfer in quantum dot pairs coupled via the Coulomb interaction are studied. Exciton transfer can be resonant or phonon-assisted. In both cases, the transfer rates strongly depend on the resonance conditions. The spin selection rules in the transfer process come from the exchange and spin-orbit interactions. The character of energy dissipation in spin transfer is different than that in the traditional spin currents. The spin-dependent photon cross-correlation functions reflect the exciton transfer process. In addition, a mathematical method to calculate F\"orster transfer in crystalline nanostructures beyond the dipole-dipole approximation is described.