General decoupling procedure for expectation values of four-operator products in electron-phonon quantum kinetics
type: Item
instance of: scholarly article
zbMATH Open document ID: 1284.82043
DOI: 10.1088/1751-8113/46/38/385302
author: Nicolas Teeny
author: Manfred Fähnle
published in: Journal of Physics A: Mathematical and Theoretical
publication date: 2013-10-23T00:00:00Z
Mathematics Subject Classification ID: 82C22
Mathematics Subject Classification ID: 34L25
Mathematics Subject Classification ID: 81U99
Mathematics Subject Classification ID: 82C10
Mathematics Subject Classification ID: 82D37
Mathematics Subject Classification ID: 82D40
zbMATH DE Number: 6218342
zbMATH Keywords: decoupling procedures
zbMATH Keywords: creation and annihilation operators
zbMATH Keywords: expectation values
zbMATH Keywords: density matrix formalism
zbMATH Keywords: semiconductors
zbMATH Keywords: demagnetization
MaRDI profile type: Publication
full work available at URL: https://doi.org/10.1088/1751-8113/46/38/385302
OpenAlex ID: W2070152381
title: General decoupling procedure for expectation values of four-operator products in electron-phonon quantum kinetics
review text: The authors derive generalized decoupling procedures for the expectation values of products of electron and phonon creation and annihilation operators. The derived procedures are valid for arbitrary electron and phonon states. In electron-phonon quantum kinetics this general procedure can be used for decoupling the four-operator products which occur when the hierarchy of infinitely many coupled equations of motion for the operator product expectation values is terminated on the level of the equations for the expectation values of three-operator products. Electron-phonon quantum kinetic effects are important for studying the coherent ultrafast dynamics on time scales shorter than about a pico-second after exciting the electrons of a solid with a short laser pulse of duration smaller than 100 femtoseconds (fs). Examples for such experiments are pulse-excited semiconductors or the fs-demagnetization of ferromagnetic films after exposure to a strong optical laser pulse.
reviewed by: Giovanni Mascali
description: scientific article; zbMATH DE number 6218342