Performance analysis of a refrigeration engine based on Coulomb coupled systems

We investigate a cryogenic non-local refrigeration set-up based on Coulomb coupled systems, that circumvents the demand for asymmetric system-to-reservoir coupling, demanded by the recently proposed non-local refrigerators. Investigating the performance and operating regime using quantum-master-equation (QME) approach, we point out that the maximum cooling power for the proposed set-up is limited to about 70% of the optimal design. In addition, we point out that to achieve a target reservoir temperature, lower compared to the average temperature of the current path, the applied voltage must be greater than a given threshold voltage, which is dependent on the reservoir temperature. Proceeding further, we demonstrate that the maximum cooling power, as well as the coefficient of performance deteriorates as one approaches a lower target reservoir temperature. The novelty of the set-up discussed here is the integration of fabrication simplicity along with descent cooling power and may pave the way towards the realization of efficient non-local cryogenic refrigeration systems.