title: Performance analysis of an irreversible quantum heat engine working with harmonic oscillators.
abstract: The cycle model of a regenerative quantum heat engine working with many noninteracting harmonic oscillators is established. The cycle consists of two isothermal and two constant-frequency processes. The performance of the cycle is investigated, based on the quantum master equation and semigroup approach. The inherent regenerative losses in the two constant-frequency processes are calculated. The expressions of several important performance parameters such as the efficiency, power output, and rate of the entropy production are derived for several interesting cases. Especially, the optimal performance of the cycle in high-temperature limit is discussed in detail. The maximum power output and the corresponding parameters are calculated. The optimal region of the efficiency and the optimal ranges of the temperatures of the working substance in the two isothermal processes are determined.
authors.affiliation: Department of Physics, Xiamen University, Xiamen 361005, People's Republic of China.
authors.forename: Bihong
authors.initials: B
authors.lastname: Lin
authors.forename: Jincan
authors.initials: J
authors.lastname: Chen