Spin Wave Diffraction Control and Read-out with a Quantum Memory for Light

TL;DR

This paper presents a method to control and read out diffracted spin waves using a quantum memory, enabling advanced manipulation of light for quantum information processing.

Contribution

It introduces a scheme for diffraction control and read-out of spin waves with a quantum memory, including dynamical control for quantum pulse sequencing.

Findings

Effective diffraction control via sinusoidal light shifts.

High-fidelity mapping between spin waves and light fields.

Applicability to hot/cold atomic vapours and solid-state systems.

Abstract

A scheme for control and read-out of diffracted spins waves to propagating light fields is presented. Diffraction is obtained via sinusoidally varying lights shifts and ideal one-to-one mapping to light is realized using a gradient echo quantum memory. We also show that dynamical control of the diffracted spin waves spatial orders can be implemented to realize a quantum pulse sequencer for temporal modes that have high time-bandwidth products. Full numerical solutions suggest that both co-propagating and couterpropagating light shift geometries can be used, making the proposal applicable to hot and cold atomic vapours as well as solid state systems with two-level atoms.