Protecting the squeezing of a two-level system by detuning in non-Markovian environments

Abstract

Squeezing of a two-level atom off-resonantly coupled to a non-Markovian reservoir is investigated. We compared two different definitions of squeezing that are based on the Heisenberg uncertainty relation and the entropy uncertainty relation and found that information entropy squeezing is more precise than variance squeezing as a measure of squeezing. Then we utilized entropy squeezing to examine the influences of the non-Markovian effect and detuning on the atomic squeezing. It is interesting to note that atomic squeezing can be protected for a long time when both the non-Markovian effect and detuning are present simultaneously. The physical mechanism is that the decay rate is suppressed much more by detuning in the non-Markovian regime than in the Markovian case.