scholarly journals Quantum thermodynamics of nanoscale steady states far from equilibrium

2018 ◽  
Vol 97 (15) ◽  
Author(s):  
Nobuhiko Taniguchi
Keyword(s):  
Steady States ◽  
Quantum Thermodynamics ◽  
Far From Equilibrium

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.

Semiconductor models for first and second order non-equilibrium phase transitions

1979 ◽  
Vol 365 (1723) ◽  
pp. 495-510 ◽  
Keyword(s):  
Phase Transitions ◽  
General Principle ◽  
Impact Ionization ◽  
Equilibrium Phase ◽  
Steady States ◽  
Second Order ◽  
Far From Equilibrium ◽  
P Type ◽  
Non Equilibrium

Non-equilibrium phase transitions in semiconductors due to impact ionization from traps have been obtained theoretically, and are discussed in detail. They include first and second order phase transitions, and develop previous work, which was restricted to second order phase transitions involving band-band processes. The models include switching transitions from non-conducting to conducting states, and from n- to p-type states. They furnish simple illustrations of the general principle that a system which is driven far from equilibrium can exhibit new stable steady states.

Possible variational principle for steady states far from equilibrium

1991 ◽  
Vol 67 (19) ◽  
pp. 2597-2600 ◽  
Author(s):  
Denis J. Evans ◽  
András Baranyai
Keyword(s):  
Variational Principle ◽  
Steady States ◽  
Far From Equilibrium

scholarly journals Far from equilibrium steady states of 1D-Schrödinger-Poisson systems with quantum wells II

2009 ◽  
Vol 61 (1) ◽  
pp. 65-106 ◽  
Author(s):  
Virginie BONNAILLIE-NOËL ◽  
Francis NIER ◽  
Yassine PATEL
Keyword(s):  
Quantum Wells ◽  
Steady States ◽  
Far From Equilibrium

scholarly journals Study of Nonequilibrium Size and Concentration Effects on the Heat and Mass Diffusion of Indistinguishable Particles Using Steepest-Entropy-Ascent Quantum Thermodynamics

2017 ◽  
Vol 139 (12) ◽  
Author(s):  
Guanchen Li ◽  
Michael R. von Spakovsky
Keyword(s):  
Spatial Scales ◽  
Local Equilibrium ◽  
Phenomenological Approach ◽  
Mass Diffusion ◽  
Nonequilibrium Process ◽  
First Principle ◽  
Quantum Thermodynamics ◽  
Concentration Effects ◽  
Nonequilibrium Processes ◽  
Far From Equilibrium

Conventional first-principle approaches for studying nonequilibrium processes depend on the mechanics of individual particles or quantum states and as a result require many details of the mechanical features of the system to arrive at a macroscopic property. In contrast, thermodynamics, which has been successful in the stable equilibrium realm, provides an approach for determining macroscopic properties without the mechanical details. Nonetheless, this phenomenological approach is not generally applicable to a nonequilibrium process except in the near-equilibrium realm and under the local equilibrium and continuum assumptions, both of which limit its ability to describe nonequilibrium phenomena. Furthermore, predicting the thermodynamic features of a nonequilibrium process (of entropy generation) across all scales is difficult. To address these drawbacks, steepest-entropy-ascent quantum thermodynamics (SEAQT) can be used. It provides a first-principle thermodynamic-ensemble based approach applicable to the entire nonequilibrium realm even that far-from-equilibrium and does so with a single kinematics and dynamics, which crosses all temporal and spatial scales. Based on prior developments by the authors, SEAQT is used here to study the heat and mass diffusion of indistinguishable particles. The study focuses on the thermodynamic features of far-from-equilibrium state evolution, which is separated from the specific mechanics of individual particle interactions. Results for nonequilibrium size (volume) and concentration effects on the evolutionary state trajectory are presented for the case of high temperature and low particle concentration, which, however, do not impact the generality of the theory and will in future studies be relaxed.

Sign in / Sign up

Export Citation Format

Share Document