Journal article

Publication year: 1999

Pages: 6371-6381

Journal: Physical Review E

Volume number: 60

Issue number: 6

ISSN: 1539-3755

eISSN: 1550-2376

Open access status: Green

DOI Link: https://doi.org/10.1103/PhysRevE.60.6371

Publisher: American Physical Society

Abstract: 
For the generalized master equations derived by Karrlein and Grabert for the microscopic model of a damped harmonic oscillator, the conditions for purity of states are written, in particular for different initial conditions and different types of damping, including Ohmic, Drude, and weak coupling cases, and the Agarwal and Weidlich-Haake models. It is shown that the states which remain pure are the squeezed states with variances that are constant in time. For pure states, generalized nonlinear Schrodinger-type equations corresponding to these master equations are also obtained. Then the condition for purity df states of a damped harmonic oscillator is considered in the framework of Lindblad theory for open quantum systems. For a special choice of the environment coefficients, correlated coherent states with constant variances and covariance are shown to be the only states which remain pure all the time during the evolution of the considered system. In Karrlein-Grabert and Lindblad models, as well as in the particular models considered, expressions for the rate of entropy production are written, and it is shown that state which preserve their purity in time are also states which minimize entropy production and, therefore, are the most stable state under evolution in the presence of the environment, and play an important role in the description of decoherence phenomenon. [S1063-651X(99)00412-2].

Harvard Citation style: Isar, A., Sandulescu, A. and Scheid, W. (1999) Purity and decoherence in the theory of a damped harmonic oscillator, Physical Review E, 60(6), pp. 6371-6381. https://doi.org/10.1103/PhysRevE.60.6371

APA Citation style: Isar, A., Sandulescu, A., & Scheid, W. (1999). Purity and decoherence in the theory of a damped harmonic oscillator. Physical Review E. 60(6), 6371-6381. https://doi.org/10.1103/PhysRevE.60.6371