Entanglement and errors in the control of spins by optical coupling

TL;DR

This paper investigates optical control of impurity spins near quantum dots, focusing on entanglement creation and error analysis due to exciton recombination, with implications for scalable quantum computing.

Contribution

It introduces a method to determine control parameters for maximizing spin entanglement and compares control errors in different regimes relevant to quantum computing.

Findings

Optimal control parameters for maximal entanglement identified

Control errors due to exciton recombination quantified

Comparison of adiabatic and nonadiabatic control errors

Abstract

We analyze the optical quantum control of impurity spins in proximity to a quantum dot. A laser pulse creates an exciton in the dot and controls the spins by indirect coupling. We show how to determine the control parameters using as an illustration the production of maximal spin entanglement. We consider errors in the quantum control due to the exciton radiative recombination. The control errors in the adiabatic and nonadiabatic case are compared to the threshold needed for scalable quantum computing.