Aspects of Quantum Energy Teleportation

TL;DR

This paper investigates quantum energy teleportation protocols at finite temperatures, analyzing entanglement's role, and introduces a measurement-based method to extract ground-state energy without quantum correlations, demonstrated on a two-qubit model.

Contribution

It presents a novel protocol for energy extraction using only measurements and classical communication, applicable even without quantum correlations.

Findings

Quantum energy teleportation can operate at finite temperatures.

Energy can be extracted from a product ground state without entanglement.

The proposed method uses only LOCC, broadening QET applicability.

Abstract

In this work, we explore quantum energy teleportation (QET) protocols, focusing on their behavior at finite temperatures , in ground and excited states. We analyze the role of entanglement as a resource for QET, particularly in thermal states, and compare the performance of QET across these initial states. We then introduce a method to extract ground-state energy through a protocol that employs only quantum measurements, local operations, and classical communication (LOCC), without requiring the ground state to be quantum correlated either through entanglement or quantum discord. To illustrate this, we propose a minimal model comprising two interacting qubits. These findings indicate that, in addition to the established QET framework where quantum correlation serves as a resource, it is possible to extract energy from an product ground state. This broadens the scope of QET's applicability across diverse quantum systems.