Performance analysis of nanostructured Peltier coolers

TL;DR

This paper analyzes the performance of nanostructured Peltier coolers using quantum transport models, revealing trade-offs, optimal barrier heights, and effects of mode transitions to guide better design.

Contribution

It provides new insights into the trade-offs and optimal conditions for nanostructured Peltier coolers, especially regarding energy barrier height and mode effects.

Findings

Optimal energy barrier height for nanowire coolers.

Cooling performance decreases with mode transition from single to multi-mode.

High coefficient of performance at low voltage bias.

Abstract

Employing non-equilibrium quantum transport models, we investigate the details and operating conditions of nano-structured Peltier coolers embedded with an energy filtering barrier. Our investigations point out non-trivial aspects of Peltier cooling which include an inevitable trade-off between the cooling power and the coefficient of performance, the coefficient of performance being high at a low voltage bias and subsequently deteriorating with increasing voltage bias. We point out that there is an optimum energy barrier height for nanowire Peltier coolers at which the cooling performance is optimized. However, for bulk Peltier coolers, the cooling performance is enhanced with the height of the energy filtering barrier. Exploring further, we point out that a degradation in cooling performance with respect to bulk is inevitable as a single moded nanowire transitions to a multi-moded one. The results discussed here can provide theoretical insights for optimal design of nano Peltier coolers.