https://doi.org/10.1007/s100530070091
Environment-induced nonclassical behaviour
1
Laboratory of Physics, Department of Chemistry, University of
Bucharest, Boulevard Carol I 13, 70346 Bucharest, Romania
2
Department of Physics, University of Bucharest, P.O. Box MG-11,
76900 Bucharest-Măgurele, Romania
Received:
22
April
1999
Revised:
2
November
1999
Published online: 15 August 2000
We analyze the transient nonclassical behaviour of a single-mode field whose interaction with an environment is governed by the quantum optical master equation. Our analytic method makes use of the generalized characteristic function of the field state. First, we find a time at which all squeezing effects disappear by decoherence regardless of the initial state of the mode. In the case of an input even coherent state, an unusual modification of higher-order squeezing at low values of thermal mean occupancy transferred to the field is found and discussed. For the same initial state, we also perform a comprehensive analysis of the mixing process during the interaction with the reservoir. We prove that a maximum in the evolution of the 2-entropy of the attenuated mode exists on condition that its initial mean photon number exceeds the mean occupancy of the reservoir. This transient mixing enhancement can be considered as a quantum effect of the initial state on the mode damping.
PACS: 42.50.Dv – Nonclassical field states; squeezed, antibunched, and sub-Poissonian states; operational definitions of the phase of the field; phase measurements / 03.65.Bz – Foundations, theory of measurement, miscellaneous theories (including Aharonov-Bohm effect, Bell inequalities, Berry's phase)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2000
