Entanglement creation in cold molecular gases using strong laser pulses

TL;DR

This paper presents a simple method to generate and detect entanglement in cold polar molecules using strong laser pulses, with potential applications in quantum information processing.

Contribution

It introduces a one-step technique to create entanglement in dilute cold molecular gases via optical pulses, enabling scalable quantum state preparation.

Findings

Maximally entangled states achieved with off-resonant pulses

Entanglement detectable through fluorescence and microwave spectra

Robustness against laser intensity fluctuations analyzed

Abstract

While many-particle entanglement can be found in natural solids and strongly interacting atomic and molecular gases, generating highly entangled states between weakly interacting particles in a controlled and scalable way presents a significant challenge. We describe here a one-step method to generate entanglement in a dilute gas of cold polar molecules. For molecules in optical traps separated by a few micrometers, we show that maximally entangled states can be created using the strong off-resonant pulses that are routinely used in molecular alignment experiments. We show that the resulting alignment-mediated entanglement can be detected by measuring laser-induced fluorescence with single-site resolution and that signatures of this molecular entanglement also appear in the microwave absorption spectra of the molecular ensemble. We analyze the robustness of these entangled molecular states with respect to intensity fluctuations of the trapping laser and discuss possible applications of the system for quantum information processing.