paper

Time-dependent restricted-active-space self-consistent-field theory for bosonic many-body systems

arXiv:1612.04419 · doi:10.1088/1367-2630/aa6319

Abstract

We describe the time-dependent restricted-active-space self-consistent-field (TD-RASSCF) method for a system of interacting bosons. We provide the theory of the method and discuss its numerical implementation. The method provides a general wavefunction based approach to solve the time-dependent and time-independent Schrödinger equation for a system of bosons. It is based on the time-dependent variational principle to optimize at each instant of time a set of time-dependent coefficients and time-dependent orbitals used to describe the total wavefunction. Including the concept of a restricted-active-space, the exponential growth of the configurational space, resulting from all possible distributions of bosons in orbitals, can be controlled trough a specific excitation scheme. We show, by illustrative time-independent and time-dependent examples, that the method provides an accurate description of the system with a substantially smaller configurational space than the one required in the multi-configurational time-dependent Hartree method for bosons (MCTDHB). The TD-RASSCF method can also tackle problems beyond the reach of the MCTDHB method when a large number of orbitals are required.

27 pages, 6 figures, 2 tables

References in corpus (19)

Cited by in corpus (26)