Exotic properties and optimal control of quantum heat engine

TL;DR

This paper investigates a quantum heat engine with a single particle in a variable potential, revealing exotic performance properties and the influence of quantum effects on efficiency, including maximum efficiency conditions and relevance to Carnot engines.

Contribution

It introduces a quantum heat engine model with unique properties and analyzes how quantum effects impact its efficiency and performance.

Findings

Maximum efficiency depends on the expansion ratio.

Lower temperatures lead to higher maximum efficiency.

The engine exhibits exotic properties not seen in classical thermodynamics.

Abstract

A quantum heat engine of a specific type is studied. This engine contains a single particle confined in the infinite square well potential with variable width and consists of three processes: the isoenergetic process (which has no classical analogs) as well as the isothermal and adiabatic processes. It is found that the engine possesses exotic properties in its performance. The efficiency takes the maximum value when the expansion ratio of the engine is appropriately set, and, in addition, the lower the temperature is, the higher the maximum efficiency becomes, highlighting aspects of the influence of quantum effects on thermodynamics. A comment is also made on the relevance of this engine to that of Carnot.