Decomposition of metric tensor in thermodynamic geometry in terms of relaxation timescales

Abstract

Usually, the Carnot efficiency cannot be achieved with finite power due to the quasi-static process, which requires infinitely slow operation speed. It is necessary to tolerate extra dissipation to obtain finite power. In the slow-driving linear response regime, this dissipation can be described as dissipated availability in a geometrical way. The key to this geometrical method is the thermodynamic length characterized by a metric tensor defined on the space of control variables. In this paper, we show that the metric tensor for Langevin dynamics can be decomposed in terms of the relaxation times of a system. As an application of the decomposition of the metric tensor, we show that it is possible to achieve Carnot efficiency at finite power by taking the vanishing limit of relaxation times without breaking trade-off relations between efficiency and power.