Entanglement of Remote Spins with Unequal Coupling to an Optically Active Mediator

TL;DR

This paper shows that two remote qubits can be entangled via an optically active mediator even with unequal coupling strengths, using both pulsed and adiabatic control methods, broadening potential experimental implementations.

Contribution

It introduces a method for entangling remote spins through an optical mediator despite unequal coupling, with both pulsed and adiabatic control schemes.

Findings

Remote spins can be entangled with unequal couplings.

Adiabatic control reduces system requirements.

The scheme is applicable to various physical systems.

Abstract

We demonstrate that two remote qubits can be entangled through an optically active intermediary even if the coupling strengths between mediator and qubits are different. This is true for a broad class of interactions. We consider two contrasting scenarios. First, we extend the analysis of a previously studied gate operation which relies on pulsed, dynamical control of the optical state and which may be performed quickly. We show that remote spins can be entangled in this case even when the intermediary coupling strengths are unequal. Second, we propose an alternative adiabatic control procedure, and find that the system requirements become even less restrictive in this case. The scheme could be tested immediately in a range of systems including molecules, quantum dots, or defects in crystals.