Influence of Indefinite Causal Order on Otto Heat Engine

2022 ◽  
Author(s):  
jifei zhao ◽  
youyang Xu
Keyword(s):  
Quantum Effect ◽  
Heat Engine ◽  
Trapped Ions ◽  
Reservoir Engineering ◽  
Quantum Thermodynamics ◽  
Causal Order ◽  
Static Efficiency ◽  
Control Qubit ◽  
Non Equilibrium

Abstract Quantum effect plays important roles in quantum thermodynamics, and recently the application of indefinite causal order to quantum thermodynamics has attracted much attentions. Based on two trapped ions, we propose a scheme to add an indefinite causal order to the isochoric cooling stroke of Otto engine through reservoir engineering. Then, we observe that the quasi-static efficiency of this heat engine is far beyond the efficiency of a normal Otto heat engine and may reach 1. When the power is its maximum, the efficiency is also much higher than that of a normal Otto heat engine. This enhancement may origin from the non-equilibrium of reservoir and the measurement on control qubit.

Application of Steepest-Entropy-Ascent Quantum Thermodynamics to Predicting Heat and Mass Diffusion From the Atomistic Up to the Macroscopic Level

2015 ◽  
Author(s):  
Guanchen Li ◽  
Michael R. von Spakovsky
Keyword(s):  
Spatial Scales ◽  
Local Equilibrium ◽  
Phenomenological Approach ◽  
Heat Diffusion ◽  
Quantum Thermodynamics ◽  
Macroscopic Property ◽  
State Evolution ◽  
Equilibrium Process ◽  
Far From Equilibrium ◽  
Non Equilibrium

Conventional first principle approaches for studying non-equilibrium or far-from-equilibrium processes all depend on the mechanics of individual particles or quantum states and as a result, require too many details of the mechanical features of the system to easily or even practically arrive at the value of a macroscopic property. In contrast, thermodynamics, which has been extremely successful in the stable equilibrium realm, provides an approach for determining a macroscopic property without going into the mechanical details. Nonetheless, such a phenomenological approach is not generally applicable to a non-equilibrium process except in the near-equilibrium realm and under the limiting local equilibrium and continuum assumptions, both of which prevent its application across all scales. To address these drawbacks, steepest-entropy-ascent quantum thermodynamics (SEAQT) can be used. It provides an ensemble-based, thermodynamics, first principles approach applicable to the entire non-equilibrium realm even that far-from-equilibrium and does so with a single kinematics and dynamics able to cross all temporal and spatial scales. Based on prior developments by the authors, this paper applies SEAQT to the study of mass and heat diffusion. Specifically, the study focuses on the thermodynamic features of far-from-equilibrium state evolution. Two kinds of size effects on the evolution trajectory, i.e., concentration and volume effects, are discussed.

Quantum Thermodynamics for the Modeling of Hydrogen Storage on a Carbon Nanotube

2008 ◽  
Author(s):  
Michael R. von Spakovsky ◽  
Charles E. Smith ◽  
Vittorio Verda
Keyword(s):  
Quantum Mechanics ◽  
Carbon Nanotube ◽  
Carbon Atom ◽  
Stable Equilibrium ◽  
Equation Of Motion ◽  
Second Law ◽  
Quantum Thermodynamics ◽  
Thermodynamic State ◽  
Hydrogen Molecules ◽  
Non Equilibrium

A typical approach for modeling systems at a nanoscale in states of non-equilibrium undergoing an irreversible process is to use an ad hoc mixture of molecular dynamics (linear and nonlinear), i.e. classical mechanics, coupled to assumptions of stable equilibrium which allow one via analogy to incorporate equilibrium thermodynamic state information such as temperature and pressure into the modeling process. However, such an approach cannot describe the actual thermodynamic evolution in state which occurs in these systems since the equation of motion used (Newton’s second law) can only describe the evolution in state from one mechanical state to another. To capture the actual thermodynamic evolution, a more general equation of motion is needed. Such an equation has been proposed, i.e. the Beretta equation of motion, as part of a general theory, which unifies (not simply bridges as is the case in statistical thermodynamics) quantum mechanics and thermodynamics. It is called the unified quantum theory of mechanics and thermodynamics or quantum thermodynamics. This equation, which strictly satisfies all of the implications of the laws of thermodynamics, including the second law, as well as of quantum mechanics, describes the thermodynamic evolution in state of a system in non-equilibrium regardless of whether or not the system is in a state far from or close to stable equilibrium. This theory and its dynamical postulate are used here to model the storage of hydrogen in an isolated box modeled in 1D and 2D with a carbon atom at one end of the box in 1D and a carbon nanotube in the middle of the box in 2D. The system is prepared in a state with the hydrogen molecules initially far from stable equilibrium, after which the system is allowed to relax (evolve) to a state of stable equilibrium. The so-called energy eigenvalue problem is used to determine the energy eigenlevels and eigenstates of the system, while the nonlinear Beretta equation of motion is used to determine the evolution of the thermodynamic state of the system as well as the spatial distributions of the hydrogen molecules in time. The results of our initial simulations show in detail the trajectory of the state of the system as the hydrogen molecules, which are initially arranged to be far from the carbon atom or the carbon nanotube, are seen to spread out in the container and eventually become more concentrated near the carbon atom or atoms.

Quantum non-gaussianity from an indefnite causal order of Gaussian operations

2021 ◽  
Author(s):  
Seid Koudia ◽  
Abdelhakim Gharbi
Keyword(s):  
Quantum Information ◽  
Quantum Key Distribution ◽  
Degrees Of Freedom ◽  
Quantum Communication ◽  
Quantum Information Processing ◽  
Quantum Metrology ◽  
Causal Order ◽  
Gaussian States ◽  
Control Qubit ◽  
Non Gaussian

Quantum non-Gaussian states are considered a useful resource for many tasks in quantum information processing, from quantum metrology and quantum sensing to quantum communication and quantum key distribution. Another useful tool that is gaining attention is the newly constructed quantum switch. Its applications in many tasks in quantum information have been proved to outperform many existing schemes in quantum communication and quantum thermometry. In this contribution, we demonstrate this to be very useful for engineering highly non-Gaussian states from Gaussian operations whose order is controlled by degrees of freedom of a control qubit. The nonconvexity of the set of Gaussian states and the set of Gaussian operations guarantees the emergence of non-Gaussianity after post-selection on the control qubit deterministically, in contrast to existing protocols in the literature. The nonclassicality of the resulting states is discussed accordingly.

scholarly journals Entropy Exchange and Thermodynamic Properties of the Single Ion Cooling Process

Entropy ◽  
2019 ◽  
Vol 21 (7) ◽  
pp. 650
Author(s):  
Jian-Guo Miao ◽  
Chun-Wang Wu ◽  
Wei Wu ◽  
Ping-Xing Chen
Keyword(s):  
Thermodynamic Properties ◽  
Heat Engine ◽  
Entropy Change ◽  
Quantum Thermodynamics ◽  
Cooling Process ◽  
Cooling Cycle ◽  
Heat Engines ◽  
Quantum Heat Engine ◽  
Ion Cooling ◽  
Complete Quantum

A complete quantum cooling cycle may be a useful platform for studying quantum thermodynamics just as the quantum heat engine does. Entropy change is an important feature which can help us to investigate the thermodynamic properties of the single ion cooling process. Here, we analyze the entropy change of the ion and laser field in the single ion cooling cycle by generalizing the idea in Reference (Phys. Rev. Lett. 2015, 114, 043002) to a single ion system. Thermodynamic properties of the single ion cooling process are discussed and it is shown that the Second and Third Laws of Thermodynamics are still strictly held in the quantum cooling process. Our results suggest that quantum cooling cycles are also candidates for the investigation on quantum thermodynamics besides quantum heat engines.

The Influence of Trapped Ions and Non-equilibrium EDF on Dust Particle Charging

2008 ◽  
Author(s):  
G. I. Sukhinin ◽  
A. V. Fedoseev ◽  
S. N. Antipov ◽  
O. F. Petrov ◽  
V. E. Fortov ◽  
...  
Keyword(s):  
Dust Particle ◽  
Trapped Ions ◽  
Particle Charging ◽  
Non Equilibrium

Trapped ions and the shielding of dust particles in low-density non-equilibrium plasma of glow discharge

2009 ◽  
Vol 42 (21) ◽  
pp. 214027 ◽  
Author(s):  
Gennady Sukhinin ◽  
Alexander Fedoseev ◽  
Sergei Antipov ◽  
Oleg Petrov ◽  
Vladimir Fortov
Keyword(s):  
Glow Discharge ◽  
Trapped Ions ◽  
Dust Particles ◽  
Low Density ◽  
Equilibrium Plasma ◽  
Non Equilibrium

Non-equilibrium thermodynamics of quantum bipartite system

2021 ◽  
pp. 2150294
Author(s):  
Kuan-Meng Zhang ◽  
Yi-Xin Chen
Keyword(s):  
Detailed Balance ◽  
Quantum Thermodynamics ◽  
Equilibrium Thermodynamics ◽  
Detailed Balance Condition ◽  
Balance Condition ◽  
Bipartite System ◽  
Hamiltonian Model ◽  
Thermodynamics And Statistical Mechanics ◽  
Non Equilibrium

In quantum information and quantum computation, a bipartite system provides a basic few-body framework for investigating significant properties of thermodynamics and statistical mechanics. A Hamiltonian model for a bipartite system is introduced to analyze the important role of interaction between bipartite subsystems in quantum non-equilibrium thermodynamics. We illustrate discrimination between such quantum thermodynamics and classical few-body non-equilibrium thermodynamics. By proposing a detailed balance condition of the bipartite system, we generally investigate the properties of the entropy and heat of our model, as well as the relation between them.

NON-EQUILIBRIUM THERMODYNAMIC ANALYSIS ON THE PERFORMANCE OF AN IRREVERSIBLE THERMALLY DRIVEN BROWNIAN MOTOR

2010 ◽  
Vol 24 (03) ◽  
pp. 325-333 ◽  
Author(s):  
TIANFU GAO ◽  
JINCAN CHEN
Keyword(s):  
Power Output ◽  
Heat Engine ◽  
Equilibrium Thermodynamics ◽  
Brownian Motors ◽  
Onsager Reciprocity ◽  
Brownian Motor ◽  
Cycle System ◽  
Thermally Driven ◽  
Onsager Reciprocity Relation ◽  
Non Equilibrium

Based on the general model of thermally-driven Brownian motors, an equivalent cycle system is established and the Onsager coefficients and efficiency at the maximum power output of the system are analytically calculated from non-equilibrium thermodynamics. It is found that the Onsager reciprocity relation holds and the Onsager coefficients are affected by the main irreversibilities existing in practical systems. Only when the heat leak and the kinetic energy change of the particle in the system are negligible, can the determinant of the Onsager matrix vanish. It is also found that in the frame of non-equilibrium thermodynamics, the power output and efficiency of an irreversible Brownian motor can be expressed to be the same form as those of an irreversible Carnot heat engine, so the results obtained here are of general significance. Moreover, these results are used to analyze the performance characteristics of a class of thermally-driven Brownian motors so that some important conclusions in literature may be directly derived from the present paper.

scholarly journals Weak invariants in dissipative systems: action principle and Noether charge for kinetic theory

2020 ◽  
Vol 378 (2170) ◽  
pp. 20190196 ◽  
Author(s):  
Sumiyoshi Abe
Keyword(s):  
Kinetic Equation ◽  
Kinetic Equations ◽  
Planck Equation ◽  
Auxiliary Field ◽  
Dissipative Systems ◽  
Quantum Thermodynamics ◽  
Symmetry Principle ◽  
Double Structure ◽  
Field Formalism ◽  
Non Equilibrium

In non-equilibrium classical thermostatistics, the state of a system may be described by not only dynamical/thermodynamical variables but also a kinetic distribution function. This ‘double structure’ bears some analogy with that in quantum thermodynamics, where both dynamical variables and the Hilbert space are involved. Recently, the concept of weak invariants has repeatedly been discussed in the context of quantum thermodynamics. A weak invariant is defined in such a way that its value changes in time but its expectation value is conserved under time evolution prescribed by a kinetic equation. Here, a new aspect of a weak invariant is revealed for the classical Fokker–Planck equation as an example of classical kinetic equations. The auxiliary field formalism is applied to the construction of the action for the kinetic equation. Then, it is shown that the auxiliary field is a weak invariant and is the Noether charge. The action is invariant under the transformation generated by the weak invariant. The result may shed light on possible roles of the symmetry principle in the kinetic descriptions of non-equilibrium systems. This article is part of the theme issue ‘Fundamental aspects of nonequilibrium thermodynamics’.

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