Chirp amplification of entropy growth in an open chirped-driven anharmonic oscillator

The dependence of decoherence on chirp is investigated in an open one-dimensional chirped-driven anharmonic oscillator. The latter is perturbed by an Ohmic environment and the decoherence of the system is measured by the linear entropy. The entropy growth is found to be significantly dependent on the value of the chirp. Especially, the curve of the entropy growth versus the chirp value has a remarkable peak, near which the decoherence of the is greatly amplified. Further analyses shows that the enhancement of the entropy growth by the chirp is closely related to the influences of the chirped drive on the energy levels participating in the quantum evolution. This can be confirmed by the correspondence between the chirp dependence of the entropy growth, the quantum spectrum and the classical squared amplitude.