Abstract

A unified theory of quantum transport processes and spectral lineshapes in condensed phases in terms of frequency-dependent dephasing rates is developed. The effective dephasing approximation (EDA) provides a self-consistent procedure for calculating the transport properties of a quantum particle in a disordered medium. It is based on mapping the averaged Liouville space propagator into the propagator of a particle moving in an ordered lattice with an effective frequency-dependent dephasing rate. The effective dephasing rate is determined self-consistently. The Liouville equation for the averaged density matrix is isomorphic to a linearized Boltzmann equation, and the effective dephasing rate represents a generalized BGK. strong-collision operator. Applications of the EDA to the Anderson model of static disorder and to a model of dynamical disorder with a finite timescale are presented, and are shown to be in agreement with scaling theories. The frequency-dependent dephasing which determines the transport processes is found to be much more sensitive to quantum localization than the dephasing which enters into the calculation of optical lineshapes and densities of states.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.