Time-reversed and coherently-enhanced memory: A single-mode quantum atom-optic memory without a cavity

Abstract

The efficiency of an ensemble-based optical quantum memory depends critically on the strength of the atom-light coupling. An optical cavity is an effective method to enhance atom-light coupling strength, with the drawback that cavities can be difficult to integrate into a memory setup. In this work we show coherent enhancement of atom-light coupling via an interference effect. The light to be absorbed into the atomic ensemble is split and used to drive the atoms from opposite ends of the ensemble. We compare this method theoretically to a cavity enhanced scheme and present experimental results for our coherent enhancement in cold rubidium-87 atoms that show an efficiency of $72\pm 5\%$ and a storage lifetime of $110\pm 10$ us.

References in corpus (12)

• Universal Approach to Optimal Photon Storage in Atomic Media
• Photon storage in Lambda-type optically dense atomic media. II. Free-space model
• Efficient and long-lived quantum memory with cold atoms inside a ring cavity
• Photon storage in Lambda-type optically dense atomic media. I. Cavity model
• Multimode Memories in Atomic Ensembles
• Cavity-enhanced storage in an optical spin-wave memory
• Analysis of a quantum memory for photons based on controlled reversible inhomogeneous broadening
• Photon echoes generated by reversing magnetic field gradients in a rubidium vapour
• Electromagnetically induced transparency and four-wave mixing in a cold atomic ensemble with large optical depth
• Induced cavities for photonic quantum gates
• Dynamical Observations of Self-Stabilising Stationary Light
• Dispersion relations for stationary light in one-dimensional atomic ensembles