Quantum scattering as a work source

TL;DR

This paper analyzes how high-energy quantum collisions can serve as a source of work, with the kinetic energy transfer acting as work performed by a time-dependent interaction, expanding quantum thermodynamics understanding.

Contribution

It identifies a regime where quantum scattering acts as a work source, linking energy transfer to work in quantum thermodynamics within scattering theory.

Findings

High-energy quantum collisions can act as work sources.

The scattering map becomes unitary and akin to a time-dependent interaction.

Kinetic energy loss corresponds to work performed during collision.

Abstract

We consider a collision between a moving particle and a fixed system, each having internal degrees of freedom. We identify the regime where the motion of the particle acts as a work source for the joint internal system, leading to energy changes which preserve the entropy. This regime arises when the particle has high kinetic energy and its quantum state of motion is broad in momentum and narrow in space, whether pure or mixed. In this case, the scattering map ruling the dynamics of the internal degrees of freedom becomes unitary and equivalent to that of a time-dependent interaction between the internal degrees of freedom of the colliding systems. It follows that the kinetic energy lost by the particle during the autonomous quantum collision coincides with the work performed by the time-dependent interaction. Recently, collisions with particles were shown to act as heat sources under suitable conditions; here we show that they can also act as work sources. This opens interesting perspectives for quantum thermodynamics formulations within scattering theory.