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Related papers: Efficiency statistics of a quantum Otto cycle

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Efficiency and power are two central measures of the performance of thermal machines. We here study the power-efficiency-stability trade-off in a finite-time quantum Carnot information engine, in which an information reservoir replaces the…

Quantum Physics · Physics 2025-09-08 Milton Aguilar , Cüneyt Ünal , Eric Lutz

We investigate the performance of an underdamped stochastic heat engine for a time-dependent harmonic oscillator. We analytically determine the optimal protocol that maximizes the efficiency at fixed power. The maximum efficiency reduces to…

Statistical Mechanics · Physics 2017-12-06 Andreas Dechant , Nikolai Kiesel , Eric Lutz

Based on quantum thermodynamic processes, we make a quantum-mechanical (QM) extension of the typical heat engine cycles, such as the Carnot, Brayton, Otto, and Diesel cycles, etc. The temperature is not included in these QM engine cycles,…

Statistical Mechanics · Physics 2013-02-05 Jianhui Wang , Yongli Ma , Jizhou He

Fluctuations strongly affect the dynamics and functionality of nanoscale thermal machines. Recent developments in stochastic thermodynamics have shown that fluctuations in many far-from-equilibrium systems are constrained by the rate of…

Quantum Physics · Physics 2021-01-29 Antoine Rignon-Bret , Giacomo Guarnieri , John Goold , Mark T. Mitchison

The Carnot statement of the second law of thermodynamics poses an upper limit on the efficiency of all heat engines. Recently, it has been studied whether generic quantum features such as coherence and quantum entanglement could allow for…

Statistical Mechanics · Physics 2015-10-14 Bartłomiej Gardas , Sebastian Deffner

We consider stochastic thermodynamics as a theory of statistical inference for experimentally observed fluctuating time-series. To that end, we introduce a general framework for quantifying the knowledge about the dynamical state of the…

Statistical Mechanics · Physics 2015-05-19 Bernhard Altaner , Jürgen Vollmer

Molecular motors are known to have the high efficiency of energy transformation in the presence of thermal fluctuation. Motivated by the surprising fact, recent studies of thermal ratchet models are showing how and when work should be…

Soft Condensed Matter · Physics 2009-10-31 Hideki Kamegawa , Tsuyoshi Hondou , Fumiko Takagi

We investigate a stochastic heat engine based on an over-damped particle diffusing on the positive real axis in an externally driven time-periodic log-harmonic potential. The periodic driving is composed of two isothermal and two adiabatic…

Statistical Mechanics · Physics 2014-05-28 Viktor Holubec

We investigate the efficiency of an isothermal Brownian work-to-work converter engine, composed of a Brownian particle coupled to a heat bath at a constant temperature. The system is maintained out of equilibrium by using two external…

Statistical Mechanics · Physics 2021-03-25 Deepak Gupta , Sanjib Sabhapandit

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…

Quantum Physics · Physics 2019-02-19 Obinna Abah , Eric Lutz

We consider a paradigmatic quantum harmonic Otto engine operating in finite time. We investigate its performance when shortcut-to-adiabaticity techniques are used to speed up its cycle. We compute efficiency and power by taking the…

Quantum Physics · Physics 2018-09-26 Obinna Abah , Eric Lutz

We study the Stoke's efficiency and its fluctuating properties in the case of a spatial asymmetric ratchet potential with a temporal asymmetric driving force from adiabatic to nonadiabatic regime. Our numerical investigations show that the…

Statistical Mechanics · Physics 2016-09-21 Mamata Sahoo , A. M Jayannavar

We consider steady state heat conduction across a quantum harmonic chain connected to reservoirs modelled by infinite collection of oscillators. The heat, $Q$, flowing across the oscillator in a time interval $\tau$ is a stochastic variable…

Statistical Mechanics · Physics 2013-05-29 Keiji Saito , Abhishek Dhar

We examine a biomolecular machine involving a driven, observable process coupled to a hidden process in a kinetically cooperative manner. A stochastic thermodynamics framework is employed to analyze a fluctuation theorem for the…

Statistical Mechanics · Physics 2025-11-14 D. Evan Piephoff , Jianshu Cao

We demonstrate that under specific conditions, a finite-time quantum Otto engine, employing a spin-1/2 particle as the working substance, despite undergoing incomplete Otto cycles, can achieve higher efficiency than an ideal quantum Otto…

Quantum Physics · Physics 2023-09-21 Debarupa Saha , Ahana Ghoshal , Ujjwal Sen

Quantization of energy is a quintessential characteristic of quantum systems. Here we analyze its effects on the operation of Otto cycle heat machines and show that energy quantization alone may alter and increase machine performance in…

A long standing open problem whether a heat engine with finite power achieves the Carnot efficiency is investigated. We rigorously prove a general trade-off inequality on thermodynamic efficiency and time interval of a cyclic process with…

Statistical Mechanics · Physics 2017-08-18 Naoto Shiraishi , Hiroyasu Tajima

We investigate a quantum heat engine with a working substance of two particles, one with a spin $1/2$ and the other with an arbitrary spin (spin $s$), coupled by Heisenberg exchange interaction, and subject to an external magnetic field.…

Quantum Physics · Physics 2016-08-07 Ferdi Altintas , Özgür E. Müstecaplıoğlu

In this paper we aim at characterizing the effect of stochastic fluctuations on the distribution of the energy exchanged by a quantum system with an external environment under sequences of quantum measurements performed at random times.…

A key focus of designing quantum thermal devices is the potential advantage that can be gleaned from genuine quantum effects when compared to classical devices. The recent experimental realization of the Pauli engine, where energy is…

Quantum Physics · Physics 2025-03-26 Keerthy Menon , Thomas Busch , Thomás Fogarty