Related papers: Spin-mechanical thermal machines
We present a self contained formalism modelled after the Brownian motion of a quantum harmonic oscillator for describing the performance of microscopic Brownian heat engines like Carnot, Stirling and Otto engines. Our theory, besides…
Recent advances in applying thermodynamic ideas to quantum systems have raised the novel prospect of using non-thermal, non-classical sources of energy, of purely quantum origin, like quantum statistics, to extract mechanical work in…
The employment of long-range interactions in quantum devices provides a promising route towards enhancing their performance in quantum technology applications. Here, the presence of long-range interactions is shown to enhance the…
We investigate the performance of a quantum thermal machine operating in finite time based on shortcut-to-adiabaticity techniques. We compute efficiency and power for a quantum harmonic Otto engine by taking the energetic cost of the…
Certain solutions of Einstein's equations in anti-de Sitter spacetime can be engineered, using extended gravitational thermodynamics, to yield `holographic heat engines', devices that turn heat into useful mechanical work. On the other…
We compare quantum Otto engines based on two different cycle models: a two-bath model, with a standard heat source and sink, and a measurement-based protocol, where the role of heat source is played by a quantum measurement. We furthermore…
In this work, we study the efficiency of charging a quantum battery through optical pumping. The battery consists of a qutrit and it is connected to a natural thermal reservoir and an external coherent drive in the limit where its upper…
We study the statistical distribution of the ergotropy and of the efficiency of a single-qubit battery ad of a single-qubit Otto engine, respectively fuelled by random collisions. The single qubit, our working fluid, is assumed to exchange…
We consider a generic four-stroke quantum Otto engine consisting of two unitary and two thermalization strokes with an arbitrary many-body working medium. Using the Schwinger-Keldysh non-equilibrium Green's function formalism, we provide an…
We consider a quantum Otto engine using an Unruh-DeWitt particle detector model which interacts with a quantum scalar field in curved spacetime. We express a generic condition for extracting positive work in terms of the effective…
The standard approach to quantum engines is based on equilibrium systems and on thermodynamic transformations between Gibbs states. However, non-equilibrium quantum systems offer enhanced experimental flexibility in the control of their…
We take advantage of the gravitational redshift experienced by a photon propagating in curved spacetime in order to construct a quantum Otto refrigeration cycle. Deriving a lower bound for the relative temperature between the cold and hot…
We propose a realization of a quantum heat engine in a hybrid microwave-optomechanical system that is the analog of a classical straight-twin engine. It exploits a pair of polariton modes that operate as out-of-phase quantum Otto cycles. A…
Quantum thermal machines can perform useful tasks, such as delivering power, cooling, or heating. In this work, we consider hybrid thermal machines, that can execute more than one task simultaneously. We characterize and find optimal…
Quantum heat engines employ as working agents multi-level systems instead of gas-filled cylinders. We consider particularly two-level agents such as electrons immersed in a magnetic field. Work is produced in that case when the electrons…
We study an Otto heat machine whose working substance is a single two-level system interacting with a cold thermal reservoir and with a squeezed hot thermal reservoir. By adjusting the squeezing or the adiabaticity parameter (the…
We put forward four schemes of coupled-qubit quantum Otto machine, a generalization of the single-qubit quantum Otto machine, based on work and heat transfer between an internal system consisting of a coupled pair of qubits and an external…
This study presents a comparative analysis of three quantum thermal engines utilizing a two-qubit Heisenberg XXZ chain as the working substance. A novel generalized quantum Otto cycle (GQOC) is introduced, featuring two distinct coupling…
Finite-time quantum heat engines are of practical relevance as they can generate finite-power, distinguishing them from ideal quasistatic engines typically used for theoretical purposes. However, these engines encounter energy losses due to…
The minimal-coupling quantum heat engine is a thermal machine consisting of an explicit energy storage system, heat baths, and a working body, which alternatively couples to subsystems through discrete strokes -- energy-conserving two-body…