Quantum coherence protection by utilizing hybrid noise

Noise is often considered as the biggest enemy of maintaining quantum coherence. However, in this paper, we show a scheme to protect quantum coherence by introducing extra noise. To be specific, we study an atom coupled to a single mode cavity (Jaynes–Cummings model) with two noises. One is from the cavity leakage, the other is from the stochastic atom-cavity coupling. Based on the non-Markovian dynamical equation, we show the quantum coherence can be protected by introducing the noise in the atom-cavity coupling. We study four different types of noises and show their performance on the coherence protection. We also analytically reveal the mechanism of the quantum coherence protection, namely the high frequency noise can freeze the dynamics thus protect coherence. Last but not least, a mixture of different types of noises (hybrid noise) is studied. We show the mixture can lower the performance of the coherence protection scheme and provide an explanation. We hope the results presented here may attract more attention on protecting quantum coherence by utilizing noise.