Work

Testing the Equivalence to Thermal States via Extractable Work under Local Operations and Classical Communication

Year: 2026

Type: article

Abstract: Understanding the thermal behavior of quantum many-body pure states is one of the most fundamental issues in quantum thermodynamics. It is widely known that typical pure states yield vanishing work, just as thermal states do, when one restricts to local operations that cannot access correlations among subsystems. However, it remains unclear whether this equivalence to thermal states persists under local operations and classical communication (LOCC), where classically accessible correlations can be exploited for work extraction. In this Letter, we establish criteria for determining whether many-body pure states remain equivalent to thermal states even under LOCC, and show that this thermal equivalence is governed by their multipartite quantum correlation structure. We show that states with asymptotically maximal multipartite entanglement, such as Haar-random states, cannot yield extensive work under LOCC, whereas some states with limited multipartite entanglement, such as constant-degree graph states, allow extensive work extraction despite being locally indistinguishable from thermal states. Thus, our Letter provides a refined operational notion of thermal equivalence beyond the traditional local regime, which is becoming increasingly important due to the recent expansion of experimentally accessible operations.

Source: Physical Review Letters

DOI: 10.1103/zsb1-gx7f

Authors: Toshihiro Yada, Nobuyuki Yoshioka, Takahiro Sagawa

Institutions: The University of Tokyo, Inamori Foundation

Language: English

Topic: Advanced Thermodynamics and Statistical Mechanics

Subfield: Statistical and Nonlinear Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green