Work extraction using Gaussian operations in non-interacting fermionic systems

TL;DR

This paper explores the potential for work extraction from non-interacting fermionic systems using Gaussian operations, identifying conditions under which passive states can be activated for work.

Contribution

It characterizes fermionic states' ability to yield work under Gaussian operations and establishes bounds on the number of passive state copies needed for activation.

Findings

Multiple copies of passive states can be activated for work extraction.

An upper bound on the number of passive state copies required was derived.

Gaussian operations enable feasible work extraction in fermionic systems.

Abstract

We investigate work extraction from non-interacting fermions under arbitrary unitary operations and the more restricted class of Gaussian unitary operations that can be feasibly implemented. We characterize general quantum states in fermionic systems according to their ability to yield work (or not) under such transformations and study the limit for which multiple copies of passive states in fermionic systems can be activated for work extraction. We find that a sufficient number of copies of non-thermal passive states can achieve this, yielding an upper bound on the number of copies needed.