Entropy production and efficiency enhancement in quantum Otto engines operating at negative temperatures
- URL: http://arxiv.org/abs/2404.02385v1
- Date: Wed, 3 Apr 2024 00:59:56 GMT
- Title: Entropy production and efficiency enhancement in quantum Otto engines operating at negative temperatures
- Authors: Aryadine F. de Sousa, Gabriella G. Damas, Norton G. de Almeida,
- Abstract summary: Cyclic classical and quantum thermal machines show higher efficiency when the strokes are carried out quasi-statically.
In this work, we make use of the concept of entropy production and friction work to explain this counterintuitive behavior.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Cyclic classical and quantum thermal machines show higher efficiency when the strokes are carried out quasi-statically. Recent theoretical and experimental work on figures of merit for thermal machines show that they have an advantage when operating in environments with negative temperatures. In an experimental proof of concept [Phys. Rev. Lett. 122, 240602 (2019)], it was shown that quantum Otto engines operating at negative temperatures can exhibit a behavior in which the faster the cycle is carried out, the higher the efficiency. In this work, we make use of the concept of entropy production and friction work to explain this counterintuitive behavior, and we show that it only occurs when reservoirs have negative temperatures.
Related papers
- Many-body enhancement in a spin-chain quantum heat engine [0.0]
We show that ferromagnetic interactions can enhance the adiabatic performance of a quantum spin chain engine at low temperatures.
The enhancement in work output is particular pronounced, increasing exponentially with interaction strength.
We identify an approximate, experimentally realisable counterdiabatic drive that can mitigate friction for weak interactions.
arXiv Detail & Related papers (2023-02-03T08:05:50Z) - Dynamical Control of Quantum Heat Engines Using Exceptional Points [0.09679987540134938]
A quantum thermal machine is an open quantum system coupled to hot and cold thermal baths.
A hallmark of non-Hermiticity is the existence of exceptional points where the eigenvalues of a non-Hermitian Hamiltonian or an Liouvillian superoperator and their associated eigenvectors coalesce.
Here, we report the experimental realisation of a single-ion heat engine and demonstrate the effect of the Liouvillian exceptional points on the dynamics and the performance of a quantum heat engine.
arXiv Detail & Related papers (2022-10-24T06:49:05Z) - Thermodynamics and Fluctuations in Quantum Heat Engines under Reservoir
Squeezing [7.109424824240926]
We show that reservoir squeezing significantly enhances the performance by increasing the thermodynamic efficiency and the power.
An experimental scheme for realizing this quantum heat engine is proposed using a single-electron spin pertaining to a trapped 40Ca$+$ ion.
arXiv Detail & Related papers (2022-09-13T11:15:31Z) - Power of a quasi-spin quantum Otto engine at negative effective
temperature [0.0]
We analyze the power output of a single-atom quantum Otto engine realized in the quasi-spin states of individual Cesium atoms.
We find that power is enhanced in the negative temperature regime, and that it reaches its maximum value at half the maximum entropy.
arXiv Detail & Related papers (2022-07-19T13:34:48Z) - Heat transport and cooling performance in a nanomechanical system with
local and non local interactions [68.8204255655161]
We study heat transport through a one dimensional time-dependent nanomechanical system.
The system presents different stationary transport regimes depending on the driving frequency, temperature gradients and the degree of locality of the interactions.
arXiv Detail & Related papers (2022-02-21T12:03:54Z) - The quantum Otto cycle in a superconducting cavity in the non-adiabatic
regime [62.997667081978825]
We analyze the efficiency of the quantum Otto cycle applied to a superconducting cavity.
It is shown that, in a non-adiabatic regime, the efficiency of the quantum cycle is affected by the dynamical Casimir effect.
arXiv Detail & Related papers (2021-11-30T11:47:33Z) - The problem of engines in statistical physics [62.997667081978825]
Engines are open systems that can generate work cyclically, at the expense of an external disequilibrium.
Recent advances in the theory of open quantum systems point to a more realistic description of autonomous engines.
We show how the external loading force and the thermal noise may be incorporated into the relevant equations of motion.
arXiv Detail & Related papers (2021-08-17T03:59:09Z) - Collective effects on the performance and stability of quantum heat
engines [62.997667081978825]
Recent predictions for quantum-mechanical enhancements in the operation of small heat engines have raised renewed interest.
One essential question is whether collective effects may help to carry enhancements over larger scales.
We study how power, efficiency and constancy scale with the number of spins composing the engine.
arXiv Detail & Related papers (2021-06-25T18:00:07Z) - Taking the temperature of a pure quantum state [55.41644538483948]
Temperature is a deceptively simple concept that still raises deep questions at the forefront of quantum physics research.
We propose a scheme to measure the temperature of such pure states through quantum interference.
arXiv Detail & Related papers (2021-03-30T18:18:37Z) - Maximal power for heat engines: role of asymmetric interaction times [110.83289076967895]
We introduce the idea of adjusting the interaction time asymmetry in order to optimize the engine performance.
Distinct optimization protocols are analyzed in the framework of thermodynamics.
arXiv Detail & Related papers (2020-12-16T22:26:14Z) - Study of quantum Otto heat engine using driven-dissipative
Schr\"{o}dinger equation [2.2559617939136505]
We study the dynamics of the quantum Otto heat engine using the driven-dissipative Schr"odinger equation.
We propose a new quantum engine working in a single reservoir to convert the pump energy into mechanical work.
arXiv Detail & Related papers (2020-10-10T00:56:23Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.