Quantum Energy Teleportation under Equilibrium and Nonequilibrium Environments

TL;DR

This paper investigates quantum energy teleportation (QET) in two-qubit systems interacting with environments, deriving analytical expressions and analyzing how nonequilibrium conditions can enhance energy transfer.

Contribution

It provides an analytical framework for QET performance in mixed states and explores environmental effects using the Redfield master equation.

Findings

Energy output often follows the most populated eigenstate.

Nonequilibrium environments can boost energy transfer under specific conditions.

Detuning and temperature differences influence the energy output.

Abstract

Quantum energy teleportation (QET), implemented via local operations and classical communication, enables carrier-free energy transfer by exploiting quantum resources. While QET has been extensively studied theoretically and validated experimentally in various quantum platforms, enhancing energy output for mixed initial states, as the system inevitably interacts with environments, remains a significant challenge. In this work, we study QET performance in a two-qubit system coupled to equilibrium or nonequilibrium reservoirs. We derive an analytical expression for the energy output in terms of the system Hamiltonian eigenstates, enabling analysis of energy output for mixed states. Using the Redfield master equation, we systematically examine the effects of qubit detuning, nonequilibrium temperature difference, and nonequilibrium chemical potential difference on the energy output. We find that the energy output for mixed states often follows that of the eigenstate with the highest population, and that nonequilibrium environments can enhance the energy output in certain parameter regimes.