Quantum refrigerators from classical kinetics

*To request access to the videoconference, email dsivak@sfu.ca

Synopsis

Quantum thermal machines build on quantum systems with the aim to achieve performance beyond classical physics. Towards this goal, models for quantum absorption refrigerators  (QAR) have been extensively explored. But what is "quantum" in such quantum thermal machines? Indeed, at the basic level quantum refrigerators are treated by kinetic Markovian master equations and as such are (hopefully!) relevant to biophysics systems. I will describe such classical models of QARs, beginning with a focus on "standard" measures such as the cooling current and efficiency. As for fluctuations, we recently derived upper and lower bounds on ratios of fluctuations of output to input currents, valid in the linear response regime, which I will describe and exemplify in the context of QARs. As time allows, I will turn to other aspects of nanoscale thermal machines, probing the impact of strong system-bath coupling and quantum coherences on their performance.

[1] D. Segal, Phys. Rev. E 97, 052145 (2018).
[2] M. Kilgour and D. Segal, Phys. Rev. E 98, 012117 (2018).
[3] S. Saryal, M. Gerry, Il. Khait, D. Segal, and B. K. Agarwalla, Phys. Rev. Lett. 127, 190603 (2021).
[4] M. Gerry, N. Kalantar, and D. Segal, arXiv:2109.03526