2018/06/30 by Yanying Liu, Yaming Yan, Meng Xu +2
Computer Science · Physics and Astronomy · #Advanced Chemical Physics Studies #Boson #Exact solutions in general relativity #Excitation #Generator (circuit theory) #Master equation #Mathematical physics #Physics #Quantum #Quantum Information and Cryptography #Quantum master equation #Quantum mechanics #Spectroscopy and Quantum Chemical Studies #Spin (aerodynamics) #quant-ph
paper · pdf · doi:10.1063/1674-0068/31/cjcp1806146
openalex created_date 2018/06/29 · openalex publication_date 2018/08/01 · arxiv created 2018/08/03 · arxiv updated 2018/10/17 · openalex updated_date 2026/08/05
The time-convolutionless (TCL) quantum master equation provides a powerful tool to simulate reduced dynamics of a quantum system coupled to a bath. The key quantity in the TCL master equation is the so-called kernel or generator, which describes effects of the bath degrees of freedom. Since the exact TCL generators are usually hard to calculate analytically, most applications of the TCL generalized master equation have relied on approximate generators using second and fourth order perturbative expansions. By using the hierarchical equation of motion (HEOM) and extended HEOM methods, we present a new approach to calculating the exact TCL generator and its high order perturbative expansions. The new approach is applied to the spin-boson model with different sets of parameters, to investigate the convergence of the high order expansions of the TCL generator. We also discuss circumstances where the exact TCL generator becomes singular for the spin-boson model, and a model of excitation energy transfer in the Fenna-Matthews-Olson complex.