Selective protected state preparation of coupled dissipative quantum emitters

TL;DR

This paper presents methods to efficiently prepare highly entangled, subradiant states in coupled quantum emitters, enhancing their potential for quantum information and precision measurement applications.

Contribution

It introduces a scheme for selective preparation of protected entangled states in coupled emitters using laser tuning and control fields, with fidelity improvements via phase engineering and magnetic fields.

Findings

Successful preparation of subradiant entangled states

Enhanced fidelity through spatial phase engineering

Improved entanglement depth with tailored magnetic fields

Abstract

Inherent binary or collective interactions in ensembles of quantum emitters induce a spread in the energy and lifetime of their eigenstates. While this typically causes fast decay and dephasing, in many cases certain special entangled collective states with minimal decay can be found, which possess ideal properties for spectroscopy, precision measurements or information storage. We show that for a specific choice of laser frequency, power and geometry or a suitable configuration of control fields one can efficiently prepare these states. We demonstrate this by studying preparation schemes for strongly subradiant entangled states of a chain of dipole-dipole coupled emitters. The prepared state fidelity and its entanglement depth is further improved via spatial excitation phase engineering or tailored magnetic fields.