Mapping approach for quantum-classical time correlation functions 1
Mapping approach for quantum-classical time correlation functions 1
Publication Type:
Journal ArticleSource:
Canadian Journal of Chemistry, Volume 87, Number 7, p.880-890 (2009)URL:
https://www.scopus.com/inward/record.uri?eid=2-s2.0-68349102130&doi=10.1139%2fV09-041&partnerID=40&md5=8029e7e9e4054fd1b36bb00582a85d31Keywords:
Computation theory, Correlation function, Correlation methods, Dynamics, Equilibrium structures, Harmonic oscillators, Many-body systems, Mapping, Oscillators (electronic), Phase space methods, Phase space representation, Quantum chemistry, Quantum correlation functions, Quantum electronics, Quantum state, Quantum subsystems, Quantum transport properties, Quantum-classical, quantum-classical dynamics, Reaction rate coefficients, Reaction rates, Simulation algorithms, Time correlation functions, Time integrals, Transport propertiesAbstract:
The calculation of quantum canonical time correlation functions is considered in this paper. Transport properties, such as diffusion and reaction rate coefficients, can be determined from time integrals of these correlation functions. Approximate quantum-classical expressions for correlation functions, which are amenable to simulation, are derived. These expressions incorporate the full quantum equilibrium structure of the system but approximate the dynamics by quantum-classical evolution where a quantum subsystem is coupled to a classical environment. The main feature of the formulation is the use of a mapping basis where the subsystem quantum states are represented by fictitious harmonic oscillator states. This leads to a full phase space representation of the dynamics that can be simulated without appeal to surface-hopping methods. The results in this paper form the basis for new simulation algorithms for the computation of quantum transport properties of large many-body systems.
