scholarly journals Entropy Production in an Elementary, Light Driven Micro-Machine

2020 ◽  
Vol 8 ◽  
Author(s):  
Stuart J. Box ◽  
Michael P. Allen ◽  
David B. Phillips ◽  
Stephen H. Simpson
Keyword(s):  
Thermodynamic Properties ◽  
Entropy Production ◽  
Optical Tweezers ◽  
Ensemble Average ◽  
Fluctuation Theorem ◽  
Second Law ◽  
Stochastic Motion ◽  
Length Scales ◽  
Intermediate Regime ◽  
Micro Machine

We consider the basic, thermodynamic properties of an elementary micro-machine operating at colloidal length scales. In particular, we track and analyze the driven stochastic motion of a carefully designed micro-propeller rotating unevenly in an optical tweezers, in water. In this intermediate regime, the second law of macroscopic thermodynamics is satisfied only as an ensemble average, and individual trajectories can be temporarily associated with decreases in entropy. We show that our light driven micro-propeller satisfies an appropriate fluctuation theorem that constrains the probability with which these apparent violations of the second law occur. Implications for the development of more complex micro-machines are discussed.

scholarly journals QUANTUM MEASUREMENTS, INFORMATION AND ENTROPY PRODUCTION

1999 ◽  
Vol 13 (28) ◽  
pp. 3369-3382 ◽  
Author(s):  
Y. N. SRIVASTAVA ◽  
G. VITIELLO ◽  
A. WIDOM
Keyword(s):  
Entropy Production ◽  
Information Entropy ◽  
Quantum Measurements ◽  
Second Law ◽  
Quantum Object ◽  
Measurement Apparatus ◽  
Thermodynamic Entropy ◽  
Classical Measurement ◽  
The Relationship

In order to understand the Landau–Lifshitz conjecture on the relationship between quantum measurements and the thermodynamic second law, we discuss the notion of "diabatic" and "adiabatic" forces exerted by the quantum object on the classical measurement apparatus. The notion of heat and work in measurements is made manifest in this approach and the relationship between information entropy and thermodynamic entropy is explored.

scholarly journals Fluctuation theorem for hidden entropy production

2013 ◽  
Vol 88 (2) ◽  
Author(s):  
Kyogo Kawaguchi ◽  
Yohei Nakayama
Keyword(s):  
Entropy Production ◽  
Fluctuation Theorem

scholarly journals Beating Carnot efficiency with periodically driven chiral conductors

2021 ◽  
Author(s):  
sungguen ryu ◽  
Rosa Lopez ◽  
L Serra ◽  
David Sanchez
Keyword(s):  
Entropy Production ◽  
Second Law Of Thermodynamics ◽  
Second Law ◽  
Fundamental Limits ◽  
Periodically Driven ◽  
Power Injection ◽  
Recent Developments ◽  
Proper Definition ◽  
Excitation Processes ◽  
Absence Of Power

Abstract Classically, the power generated by an ideal thermal machine cannot be larger than the Carnot limit. This profound result is rooted in the second law of thermodynamics. A hot question is whether this bound is still valid for microengines operating far from equilibrium. Here, we demonstrate that a quantum chiral conductor driven by AC voltage can indeed work with efficiencies much larger than the Carnot bound. The system also extracts work from common temperature baths, violating Kelvin-Planck statement. Nonetheless, with the proper definition, entropy production is always positive and the second law is preserved. The crucial ingredients to obtain efficiencies beyond the Carnot limit are: i) irreversible entropy production by the photoassisted excitation processes due to the AC field and ii) absence of power injection thanks to chirality. Our results are relevant in view of recent developments that use small conductors to test the fundamental limits of thermodynamic engines.

Quantum Coherences as a Thermodynamic Potential

2019 ◽  
Vol 26 (04) ◽  
pp. 1950022
Author(s):  
César A. Rodríguez-Rosario ◽  
Thomas Frauenheim ◽  
Alán Aspuru-Guzik
Keyword(s):  
Entropy Production ◽  
Quantum Transport ◽  
Thermodynamic Potential ◽  
Quantum Measurements ◽  
Second Law ◽  
General Sense ◽  
Thermodynamic Potentials ◽  
General Systems ◽  
Thermodynamic Effects

Here we demonstrate how the interplay between quantum coherences and a decoherence bath, such as one given by continuos quantum measurements, lead to new kinds of thermodynamic potentials and flows. We show how a mathematical extension of thermodynamics includes decoherence baths leading to a more general sense of the zeroth and first law. We also show how decoherence adds contributions to the change in entropy production in the second law. We derive a thermodynamic potential that depends only on the interplay between quantum coherences and a decoherence thermodynamic bath. This leads to novel thermodynamic effects, such as Onsager relationships that depend on quantum coherences. This provides a thermodynamics interpretation of the role of decoherence on quantum transport in very general systems.

DIFFUSION IN MULTICOMPONENT METALLIC SYSTEMS: VI. SOME THERMODYNAMIC PROPERTIES OF THE D MATRIX AND THE CORRESPONDING SOLUTIONS OF THE DIFFUSION EQUATIONS

1963 ◽  
Vol 41 (12) ◽  
pp. 2166-2173 ◽  
Author(s):  
J. S. Kirkaldy ◽  
D. Weichert ◽  
Zia-Ul- Haq
Keyword(s):  
Free Energy ◽  
Thermodynamic Properties ◽  
Stability Condition ◽  
Stable Solution ◽  
Positive Definite ◽  
Diffusion Equations ◽  
Second Law ◽  
Isothermal Diffusion ◽  
Gibb’S Free Energy ◽  
The Stability

The second law requirement that the Onsager L matrix for isothermal diffusion in a stable solution be positive definite and the stability condition for such a solution that the Hessian of the Gibb's free energy be positive definite impose on the diffusion D matrix the condition that it always have real and positive eigenvalues. This condition ensures that solutions of the differential equations for diffusion will always relax in a nonperiodic way.

scholarly journals Intermediate scattering function of an anisotropic active Brownian particle

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Christina Kurzthaler ◽  
Sebastian Leitmann ◽  
Thomas Franosch
Keyword(s):  
Brownian Particle ◽  
Rotational Diffusion ◽  
Effective Diffusion ◽  
Mean Square Displacement ◽  
Scattering Function ◽  
Directed Motion ◽  
Stochastic Motion ◽  
Length Scales ◽  
Intermediate Scattering Function ◽  
Active Brownian Particle

Abstract Various challenges are faced when animalcules such as bacteria, protozoa, algae, or sperms move autonomously in aqueous media at low Reynolds number. These active agents are subject to strong stochastic fluctuations, that compete with the directed motion. So far most studies consider the lowest order moments of the displacements only, while more general spatio-temporal information on the stochastic motion is provided in scattering experiments. Here we derive analytically exact expressions for the directly measurable intermediate scattering function for a mesoscopic model of a single, anisotropic active Brownian particle in three dimensions. The mean-square displacement and the non-Gaussian parameter of the stochastic process are obtained as derivatives of the intermediate scattering function. These display different temporal regimes dominated by effective diffusion and directed motion due to the interplay of translational and rotational diffusion which is rationalized within the theory. The most prominent feature of the intermediate scattering function is an oscillatory behavior at intermediate wavenumbers reflecting the persistent swimming motion, whereas at small length scales bare translational and at large length scales an enhanced effective diffusion emerges. We anticipate that our characterization of the motion of active agents will serve as a reference for more realistic models and experimental observations.

scholarly journals Entropy production and the Second Law in photosynthesis

2007 ◽  
Vol 1767 (10) ◽  
pp. 1189-1193 ◽  
Author(s):  
Robert S. Knox ◽  
William W. Parson
Keyword(s):  
Entropy Production ◽  
Second Law
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