Generating sustained coherence in a quantum memory for retrieval at the times of quantum revival

TL;DR

This paper investigates the time degradation of quantum information in an optomechanical quantum memory with nonlinearities, identifying parameter regimes where information can be retrieved without degradation despite environmental dissipation.

Contribution

It introduces a detailed analysis of quantum memory degradation considering nonlinearities and proposes parameter conditions for perfect information retrieval during quantum revival.

Findings

Identifies parameter regimes for degradation-free information retrieval.

Shows that nonlinearity can be negligible, making retrieval independent of coherence revival time.

Demonstrates the impact of dissipation on quantum memory coherence and amplitude loss.

Abstract

We study the time degradation of quantum information stored in a quantum memory device under a dissipative environment in a parameter range which is experimentally relevant. The quantum memory under consideration comprises of an optomechanical system with additional Kerr non-linearity in the optical mode and an anharmonic mechanical oscillator with quadratic non-linearity. Time degradation is monitored, both in terms of loss of coherence which is analyzed with the help of Wigner functions, as well as in terms of loss of amplitude of the original state studied as a function of time. While our time trajectories explore the degree to which the stored information degrades depending upon the variation in values of various parameters involved, we suggest a set of parameters for which the original information can be retrieved without degradation. We come across a highly attention seeking situation where the role played by the non-linearity is insignificant and the system behaves as if the information is stored in a linear medium. For this case, the information retrieval is independent of the coherence revival time and can be retrieved at any instant during the time evolution.