Stochastic resonance of quantum discord

Abstract

We study the stochastic resonance of quantum discord ("discord resonance") in coupled quantum systems and make a comparison with the stochastic resonance of entanglement ("entanglement resonance"). It is found that the discord resonance is much more robust against dephasing noise and thermal effects than the entanglement resonance. We also show that, unlike the entanglement resonance, the level of dissipation at which the discord resonance occurs is not sensitive to dephasing noise. These results suggest that it is easier to detect the discord resonance in actual experiments, where the dephasing noise and temperature are difficult to control. © 2011 American Physical Society.