Multi-Modal Properties and Dynamics of the Gradient Echo Quantum Memory

TL;DR

This paper explores the properties of Gradient Echo Memory (GEM), revealing its ability to preserve complex signals and function as a high-fidelity multi-mode quantum memory through a polariton-based description.

Contribution

It introduces a polariton-based dynamic model of GEM, demonstrating its robustness and high-fidelity multi-mode storage capabilities at various optical depths.

Findings

GEM can be described by polaritons in k-space.

It accurately preserves signals with large time-bandwidth products.

At high optical depths, GEM functions as a high-fidelity multi-mode quantum memory.

Abstract

We investigate the properties of a recently proposed Gradient Echo Memory (GEM) scheme for information mapping between optical and atomic systems. We show that GEM can be described by the dynamic formation of polaritons in k-space. This picture highlights the flexibility and robustness with regards to the external control of the storage process. Our results also show that, as GEM is a frequency-encoding memory, it can accurately preserve the shape of signals that have large time-bandwidth products, even at moderate optical depths. At higher optical depths, we show that GEM is a high fidelity multi-mode quantum memory.