scholarly journals An Application of the Madelung Formalism for Dissipating and Decaying Systems

Symmetry ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 812
Author(s):  
Maedeh Mollai ◽  
Seyed Majid Saberi Fathi
Keyword(s):  
Quantum Physics ◽  
Quantum Dissipative Systems ◽  
Dissipative Systems ◽  
Quantum Dissipation ◽  
Modeling And Analysis ◽  
Convection Diffusion ◽  
Continuity Equations ◽  
Diffusion Effects ◽  
Diffusion Phenomena ◽  
And Diffusion

This paper is concerned with the modeling and analysis of quantum dissipation and diffusion phenomena in the Schrödinger picture. We derive and investigate in detail the Schrödinger-type equations accounting for dissipation and diffusion effects. From a mathematical viewpoint, this equation allows one to achieve and analyze all aspects of the quantum dissipative systems, regarding the wave equation, Hamilton–Jacobi and continuity equations. This simplification requires the performance of “the Madelung decomposition” of “the wave function”, which is rigorously attained under the general Lagrangian justification for this modification of quantum mechanics. It is proved that most of the important equations of dissipative quantum physics, such as convection-diffusion, Fokker–Planck and quantum Boltzmann, have a common origin and can be unified in one equation.

Transport and fluctuations in nonlinear-dissipative systems: role of interparticle collisions

1999 ◽  
Vol 4 ◽  
pp. 31-86 ◽  
Author(s):  
R. Katilius ◽  
A. Matulionis ◽  
R. Raguotis ◽  
I. Matulionienė
Keyword(s):  
Electric Fields ◽  
Carrier Density ◽  
Experimental Results ◽  
Dissipative Systems ◽  
Doped Semiconductors ◽  
Electron Diffusion ◽  
Electron Collisions ◽  
Electric Noise ◽  
Diffusion Phenomena

The goal of the paper is to overview contemporary theoretical and experimental research of the microwave electric noise and fluctuations of hot carriers in semiconductors, revealing sensitivity of the noise spectra to non-linearity in the applied electric field strength and, especially, in the carrier density. During the last years, investigation of electronic noise and electron diffusion phenomena in doped semiconductors was in a rapid progress. By combining analytic and Monte Carlo methods as well as the available experimental results on noise, it became possible to obtain the electron diffusion coefficients in the range of electric fields where inter-electron collisions are important and Price’s relation is not necessarily valid. Correspondingly, a special attention to the role of inter-electron collisions and of the non-linearity in the carrier density while shaping electric noise and diffusion phenomena in the non-equilibrium states will be paid. The basic and up-to-date information will be presented on methods and advances in this contemporary field - the field in which methods of non-linear analytic and computational analysis are indispensable while seeking coherent understanding and interpretation of experimental results.

On the Role of Charged Defect States and Deep Traps in the Photocarrier Drift and Diffusion in a-Si:H

2000 ◽  
Vol 609 ◽  
Author(s):  
Paul Stradins ◽  
Akihisa Matsuda
Keyword(s):  
Particle Number ◽  
Defect States ◽  
Total Electron ◽  
Minority Carrier Diffusion Length ◽  
Continuity Equations ◽  
Effective Mobility ◽  
Almost All ◽  
Charged Defects ◽  
And Diffusion

ABSTRACTThe drift and diffusion in the presence of charged defects and photocarriers trapped in the tail states is re-examined. In continuity equations, diffusive and drift currents are related to free particles while the Poisson equation includes all charges. In order to make use of ambipolar diffusion approximation, the mobilities and diffusion coefficients should be attributed to the total electron and hole populations making them strongly particle-number dependent. Due to the asymmetry of the conduction and valence band tails, almost all trapped electrons reside in negatively charged defects (D−). A simple model of photocarrier traffic via tail and defect states allows to establish the effective mobility values and coefficients in Einstein relations. In a photocarrier grating experiment, grating of D− is counterbalanced by the grating of trapped holes. Nevertheless, electrons remain majority carriers, allowing the measurement of minority carrier diffusion length, but analysis is needed to relate the latter with μτ product.

scholarly journals Effects of transient temperature on human's heat losses

2016 ◽  
Vol 20 (3) ◽  
pp. 827-830
Author(s):  
Lijuan Wang ◽  
Yuhui Di ◽  
Hui Yin ◽  
Yanfeng Liu ◽  
Jiaping Liu
Keyword(s):  
Energy Balance ◽  
Air Conditioning ◽  
Heat Losses ◽  
Linear Functions ◽  
Quadratic Functions ◽  
Balance Model ◽  
Transient Temperature ◽  
Convection Diffusion ◽  
Comfort Evaluation ◽  
And Diffusion

The objectives of the paper are to analyze human convection, radiation, evaporation, respiration, conduction, and diffusion heat losses when the operative temperature increases from 26-34.4?C and then decreases from 34.4-26?C with a ratio of 1.4?C per 5 minutes. A energy balance model is used for sedentary subject. The results show that during temperature rising, all the heat losses are linear functions of temperature, while during temperature dropping, the convection, diffusion, and respiration heat losses are quadratic functions of temperature. The results are useful for thermal comfort evaluation and heating, ventilation, and air conditioning design.

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