# Correlation approach to work extraction from finite quantum systems

@article{Giorgi2015CorrelationAT, title={Correlation approach to work extraction from finite quantum systems}, author={Gian Luca Giorgi and Steve Campbell}, journal={Journal of Physics B: Atomic, Molecular and Optical Physics}, year={2015}, volume={48} }

Reversible work extraction from identical quantum systems via collective operations was shown to be possible even without producing entanglement among the sub-parts. Here, we show that implementing such global operations necessarily imply the creation of quantum correlations, as measured by quantum discord. We also reanalyze the conditions under which global transformations outperform local gates as far as maximal work extraction is considered by deriving a necessary and sufficient condition…

## 24 Citations

### Optimal Work Extraction and Thermodynamics of Quantum Measurements and Correlations.

- PhysicsPhysical review letters
- 2018

This work focuses on the work that can be obtained by exploiting the correlations shared between the system of interest and an additional ancilla, where measurement backaction introduces a nontrivial thermodynamic tradeoff.

### Trade-off Between Work and Correlations in Quantum Thermodynamics

- Physics
- 2018

The role of correlations in quantum thermodynamics is reviewed, with a particular focus on the conversion of work into correlations, and new insights are provided into the fundamental work cost of correlations and the existence of optimally correlating unitaries.

### Trade-off Between Work and Correlations in Quantum Thermodynamics

- Physics
- 2019

Quantum thermodynamics and quantum information are two frameworks for employing quantum mechanical systems for practical tasks, exploiting genuine quantum features to obtain advantages with respect…

### Work extraction and fully entangled fraction

- Physics
- 2017

For a bipartite state with equal local dimension d, we prove that one can obtain work gain under Landauer's erasure process on one party in identically and independently distributed (iid) limit when…

### Quantum Coherence and Ergotropy.

- PhysicsPhysical review letters
- 2020

This work identifies a coherent contribution to the ergotropy (the maximum amount of unitarily extractable work via cyclical variation of Hamiltonian parameters) and shows this by dividing the optimal transformation into an incoherent operation and a coherence extraction cycle.

### Multipartite quantum and classical correlations in symmetric n-qubit mixed states

- PhysicsQuantum Inf. Process.
- 2016

It is shown that the existence of symmetries greatly reduces the amount of free parameters to be optimized in order to find the optimal measurement that minimizes the conditional entropy in the discord calculation.

### Local passivity and entanglement in shared quantum batteries

- PhysicsPhysical Review A
- 2021

We identify the conditions for local passivity for shared quantum batteries with local Hamiltonians. For locally passive states of two-qubit batteries, we find the relation of their entanglement…

### Quantum correlated heat engine in XY chain with Dzyaloshinskii–Moriya interactions

- PhysicsScientific reports
- 2022

In this paper, we consider a heat engines composed of two interactional qubits with spin-orbit interaction (Dzyaloshinskii–Moriya (DM)) subject to an external magnetic field, so that each qubit is…

### Quantum Features and Signatures of Quantum Thermal Machines

- Physics
- 2018

The aim of this book chapter is to indicate how quantum phenomena are affecting the operation of microscopic thermal machines, such as engines and refrigerators. As converting heat to work is one of…

### Quantacell: powerful charging of quantum batteries

- Physics
- 2015

It is demonstrated that the quantum advantage for power holds when, with cyclic operation in mind, initial and final states are required to be separable.

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