Dissipative systems: on the natural inclusion of radiation loss in the quantized electromagnetic field

1987 ◽  
Vol 65 (4) ◽  
pp. 359-364 ◽  
Author(s):  
B. Baseia ◽  
F. J. B. Feitosa ◽  
A. Liberato
Keyword(s):  
Electromagnetic Field ◽  
Initial Conditions ◽  
Optical Cavity ◽  
Radiation Loss ◽  
Dissipative Systems ◽  
Mixed States ◽  
Natural Inclusion ◽  
Quantized Electromagnetic Field ◽  
Quantized Radiation Field ◽  
Natural Way

The inclusion of damping in the quantized radiation field in pure and mixed states is accomplished in a natural way, without using traditional loss reservoirs, through the application of appropriate boundary conditions in a simple model of an optical cavity coupled to the outside world. By using collective operators (which are suitable weighted superpositions of the usual creation and annihilation operators for modes of the continuous spectrum, extended over each Fox–Li band) and convenient initial conditions, we are able to describe the radiation loss from an optical cavity to the outside world. The physical situations corresponding to initial conditions leading to the exponential damping are also investigated.

Laser theory with natural inclusion of radiation loss: Density-operator approach

1988 ◽  
Vol 66 (9) ◽  
pp. 764-768 ◽  
Author(s):  
A. Liberato ◽  
B. Baseia
Keyword(s):  
Recent Result ◽  
Density Operator ◽  
Conventional Treatment ◽  
Optical Cavity ◽  
Equation Of Motion ◽  
Operator Approach ◽  
Transmitted Beam ◽  
Laser Theory ◽  
Natural Inclusion ◽  
Natural Way

A recent result of a previous paper describing the field loss in an optical cavity in a natural way is applied to laser theory. The field loss, due to the transmitted beam light, and the field gain, now attributed to the presence of active atoms but previously attributed to two noninteracting mechanisms, are correctly added to provide the equation of motion for the density operator of the radiation field. The replacement of individual operators, which appear in the conventional treatment, with collective operators is a conceptual difference that emerges from the present approach.

scholarly journals Internal volumetric heat generation and heat capacity prediction during a material electromagnetic treatment process using hybrid algorithms

2018 ◽  
Vol 38 (1) ◽  
pp. 74-82
Author(s):  
Edgar García-Morantes ◽  
Iván Amaya-Contreras ◽  
Rodrigo Correa-Cely
Keyword(s):  
Inverse Problem ◽  
Heat Capacity ◽  
Electromagnetic Field ◽  
Heat Generation ◽  
Initial Conditions ◽  
Limited Range ◽  
First Case ◽  
Realistic Situation ◽  
Wide Range ◽  
Volumetric Heat Generation

This work considers the estimation of internal volumetric heat generation, as well as the heat capacity of a solid spherical sample, heated by a homogeneous, time-varying electromagnetic field. To that end, the numerical strategy solves the corresponding inverse problem. Three functional forms (linear, sinusoidal, and exponential) for the electromagnetic field were considered. White Gaussian noise was incorporated into the theoretical temperature profile (i.e. the solution of the direct problem) to simulate a more realistic situation. Temperature was pretended to be read through four sensors. The inverse problem was solved through three different kinds of approach: using a traditional optimizer, using modern techniques, and using a mixture of both. In the first case, we used a traditional, deterministic Levenberg-Marquardt (LM) algorithm. In the second one, we considered three stochastic algorithms: Spiral Optimization Algorithm (SOA), Vortex Search (VS), and Weighted Attraction Method (WAM). In the final case, we proposed a hybrid between LM and the metaheuristics algorithms. Results show that LM converges to the expected solutions only if the initial conditions (IC) are within a limited range. Oppositely, metaheuristics converge in a wide range of IC but exhibit low accuracy. The hybrid approaches converge and improve the accuracy obtained with the metaheuristics. The difference between expected and obtained values, as well as the RMS errors, are reported and compared for all three methods.

Interaction of an atom with the quantized electromagnetic field

2012 ◽  
pp. 457-497
Author(s):  
Gilbert Grynberg ◽  
Alain Aspect ◽  
Claude Fabre ◽  
Claude Cohen-Tannoudji
Keyword(s):  
Electromagnetic Field ◽  
Quantized Electromagnetic Field

Quantum vacuum torque on a bi-anisotropic absorbing magneto-dielectric cylindrical shell co-axis with a perfectly conductor cylindrical shell

2019 ◽  
Vol 34 (26) ◽  
pp. 1950149
Author(s):  
Marzieh Hossein Zadeh ◽  
Majid Amooshahi
Keyword(s):  
Cylindrical Shell ◽  
Electromagnetic Field ◽  
Angular Momentum ◽  
Thermal State ◽  
Canonical Quantization ◽  
Vacuum State ◽  
Quantum Vacuum ◽  
Ladder Operators ◽  
Quantized Electromagnetic Field ◽  
Series Technique

A fully canonical quantization of electromagnetic field in the presence of a bi-anisotropic absorbing magneto-dielectric cylindrical shell is provided. The mode expansions of the dynamical quantum fields, contained in the theory, is achieved and the ladder operators of the system are introduced. Using the Frobenius’s series technique, the Maxwell’s equations in the presence of the bi-anisotropic absorbing magneto-dielectric cylindrical shell are solved and the space–time dependence of the quantized electromagnetic field is obtained. Applying the conservation principle of the angular momentum, the net quantum vacuum torque exerted on the bi-anisotropic absorbing magneto-dielectric cylindrical shell is calculated. The net quantum vacuum torque exerted on the cylindrical shell is calculated in the vacuum state and the thermal state of the system. The quantum vacuum torque on the cylindrical shell identically vanishes when the bi-anisotropic absorbing magneto-dielectric cylindrical shell is converted to an isotropic one.

Efficient Numerical Shadowing Global Error Estimation for High Dimensional Dissipative Systems

2004 ◽  
Vol 4 (2) ◽  
Author(s):  
Jon Collis ◽  
Erik S. Van Vleck
Keyword(s):  
Error Estimation ◽  
Initial Conditions ◽  
Efficient Estimation ◽  
Global Error ◽  
Dissipative Systems ◽  
High Dimensional ◽  
Initial Value ◽  
Small Perturbations ◽  
One Step ◽  
Global Error Estimation

AbstractShadowing is a means of characterizing global errors in the numerical solution of initial value differential equations by allowing for small perturbations in the initial conditions. The method presented in this paper provides a technique for efficient estimation of the shadowing global error for systems that have a large number of exponentially decaying modes. The method is formulated for one-step methods and is applied to the spatial discretization of some dissipative PDEs.

Sign in / Sign up

Export Citation Format

Share Document