Theoretical aspects of quantum state transfer, correlation measurement and electron-nuclei coupled dynamics in quantum dots

TL;DR

This paper explores the physics of quantum state transfer, correlation measurement, and electron-nuclei interactions in quantum dots, proposing methods for high-fidelity quantum communication and revealing new quantum phenomena.

Contribution

It analyzes the conditions for high-fidelity quantum state transfer, proposes an optical Bell measurement method, and predicts novel correlation phenomena in electron-nuclei coupled systems.

Findings

Conditions for high-fidelity quantum state transfer clarified

Feasibility of optical Bell measurement confirmed

Predicted bunching and revival phenomena in electron spin measurements

Abstract

Photons and electrons are the key quantum media for the quantum information processing based on solid state devices. The essential ingredients to accomplish the quantum repeater were investigated and their underlying physics were revealed. The relevant elementary processes of the quantum state transfer between a single photon and a single electron were analyzed, to clarify the conditions to be satisfied to achieve the high fidelity of the quantum state transfer. An optical method based on the Faraday rotation was proposed to carry out the Bell measurement of two electrons which is a key operation in the entanglement swapping for the quantum repeater and its feasibility was confirmed. Also investigated was the quantum dynamics in the electron-nuclei coupled spin system in quantum dots and a couple of new phenomena were predicted related to the correlations induced by the hyperfine interaction, namely, bunching and revival in the electron spin measurements. These findings will pave the way to accomplish the efficient and robust quantum repeater and nuclear spin quantum memory.