Towards a Realistic Model for Cavity-Enhanced Atomic Frequency Comb Quantum Memories

TL;DR

This paper presents a comprehensive theoretical model for cavity-enhanced atomic frequency comb quantum memories that incorporates dispersion effects, aligning well with experimental data and improving efficiency predictions.

Contribution

The authors develop a new theoretical model that includes dispersion effects, providing more accurate efficiency estimates for cavity-enhanced AFC quantum memories.

Findings

Model aligns closely with experimental results

Dispersion inclusion improves efficiency prediction

Accurately estimates comb properties like optical depth

Abstract

Atomic frequency comb (AFC) quantum memory is a favorable protocol in long distance quantum communication. Putting the AFC inside an asymmetric optical cavity enhances the storage efficiency but makes the measurement of the comb properties challenging. We develop a theoretical model for cavity-enhanced AFC quantum memory that includes the effects of dispersion, and show a close alignment of the model with our own experimental results. Providing semi quantitative agreement for estimating the efficiency and a good description of how the efficiency changes as a function of detuning, it also captures certain qualitative features of the experimental reflectivity. For comparison, we show that a theoretical model without dispersion fails dramatically to predict the correct efficiencies. Our model is a step forward to accurately estimating the created comb properties, such as the optical depth inside the cavity, and so being able to make precise predictions of the performance of the prepared cavity-enhanced AFC quantum memory.