Isar, A. The harmonic oscillator with dissipation within the theory of open quantum systems. (English) Zbl 0861.60097 Helv. Phys. Acta 67, No. 4, 436-449 (1994). Summary: Time evolution of the expectation values of various dynamical operators of the harmonic oscillator with dissipation is analytically obtained within the framework of the Lindblad theory for open quantum systems. We deduce the density matrix of the damped harmonic oscillator from the solution of the Fokker-Planck equation for the coherent state representation, obtained from the master equation for the density operator. The Fokker-Planck equation for the Wigner distribution function, subject to either the Gaussian type or the \(\delta\)-function type of initial conditions, is also solved by using the Wang-Uhlenbeck method. The obtained Wigner functions are two-dimensional Gaussians with different widths. Cited in 4 Documents MSC: 60K40 Other physical applications of random processes 82C31 Stochastic methods (Fokker-Planck, Langevin, etc.) applied to problems in time-dependent statistical mechanics Keywords:harmonic oscillator; open quantum systems; Fokker-Planck equation; Wigner distribution; Wang-Uhlenbeck method PDFBibTeX XMLCite \textit{A. Isar}, Helv. Phys. Acta 67, No. 4, 436--449 (1994; Zbl 0861.60097) Full Text: arXiv