title: Universality of efficiency at unified trade-off optimization.
abstract: We calculate the efficiency at the unified trade-off optimization criterion (the so-called maximum Ω criterion) representing a compromise between the useful energy and the lost energy of heat engines operating between two reservoirs at different temperatures and chemical potentials, and demonstrate that the linear coefficient 3/4 and quadratic coefficient 1/32 of the efficiency at maximum Ω are universal for heat engines under strong coupling and symmetry conditions. It is further proved that the conclusions obtained here also apply to the ecological optimization criterion.
authors.affiliation: Department of Physics, Xiamen University, Xiamen 361005, People's Republic of China.
authors.forename: Yanchao
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Physics, Xiamen University, Xiamen 361005, People's Republic of China.
authors.forename: Chuankun
authors.initials: C
authors.lastname: Huang
authors.affiliation: Department of Physics, Xiamen University, Xiamen 361005, People's Republic of China.
authors.forename: Guoxing
authors.initials: G
authors.lastname: Lin
authors.affiliation: Department of Physics, Xiamen University, Xiamen 361005, People's Republic of China.
authors.forename: Jincan
authors.initials: J
authors.lastname: Chen