Time-dependent quantum many-body theory of identical bosons in a double well: Early-time ballistic interferences of fragmented and number entangled states

Journal Article · Mon Oct 15 00:00:00 EDT 2007 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.76.043612· OSTI ID:21020779

Masiello, David J; Reinhardt, William P ^[1]

---

1. Department of Chemistry, University of Washington, Seattle, Washington 98195-1700 (United States)

A time-dependent multiconfigurational self-consistent field theory is presented to describe the many-body dynamics of a gas of identical bosonic atoms confined to an external trapping potential at zero temperature from first principles. A set of generalized evolution equations are developed, through the time-dependent variational principle, which account for the complete and self-consistent coupling between the expansion coefficients of each configuration and the underlying one-body wave functions within a restricted two state Fock space basis that includes the full effects of the condensate's mean field as well as atomic correlation. The resulting dynamical equations are a classical Hamiltonian system and, by construction, form a well-defined initial value problem. They are implemented in an efficient numerical algorithm. An example is presented, highlighting the generality of the theory, in which the ballistic expansion of a fragmented condensate ground state is compared to that of a macroscopic quantum superposition state, taken here to be a highly entangled number state, upon releasing the external trapping potential. Strikingly different many-body matter-wave dynamics emerge in each case, accentuating the role of both atomic correlation and mean-field effects in the two condensate states.

• OSTI ID: 21020779
• Journal Information: Physical Review. A, Vol. 76, Issue 4; Other Information: DOI: 10.1103/PhysRevA.76.043612; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALGORITHMS
BOSE-EINSTEIN CONDENSATION
BOSONS
CONFIGURATION INTERACTION
CORRELATIONS
COUPLING
EQUATIONS
GROUND STATES
HAMILTONIANS
INTERFERENCE
MANY-BODY PROBLEM
MEAN-FIELD THEORY
POTENTIALS
QUANTUM ENTANGLEMENT
SELF-CONSISTENT FIELD
TIME DEPENDENCE
VARIATIONAL METHODS
WAVE FUNCTIONS