Article

Single-particle density matrix for a time-dependent strongly interacting one-dimensional Bose gas

Physical Review A (Impact Factor: 2.99). 07/2009; 80(5). DOI: 10.1103/PhysRevA.80.053616
Source: arXiv

ABSTRACT We derive a $1/c$-expansion for the single-particle density matrix of a
strongly interacting time-dependent one-dimensional Bose gas, described by the
Lieb-Liniger model ($c$ denotes the strength of the interaction). The formalism
is derived by expanding Gaudin's Fermi-Bose mapping operator up to $1/c$-terms.
We derive an efficient numerical algorithm for calculating the density matrix
for time-dependent states in the strong coupling limit, which evolve from a
family of initial conditions in the absence of an external potential. We have
applied the formalism to study contraction dynamics of a localized wave packet
upon which a parabolic phase is imprinted initially.

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