P Deuar and P D Drummond 2006 J. Phys. A: Math. Gen. 39 1163 doi:10.1088/0305-4470/39/5/010
P Deuar and P D Drummond
Show affiliationsThe performance of the positive P phase-space representation for exact many-body quantum dynamics is investigated. Gases of interacting bosons are considered, where the full quantum equations to simulate are of a Gross–Pitaevskii form with added Gaussian noise. This method gives tractable simulations of many-body systems because the number of variables scales linearly with the spatial lattice size. An expression for the useful simulation time is obtained, and checked in numerical simulations. The dynamics of first-, second- and third-order spatial correlations are calculated for a uniform interacting 1D Bose gas subjected to a change in scattering length. Propagation of correlations is seen. A comparison is made with other recent methods. The positive P method is particularly well suited to open systems as no conservation laws are hard-wired into the calculation. It also differs from most other recent approaches in that there is no truncation of any kind.
03.75.Kk Dynamic properties of condensates; collective and hydrodynamic excitations, superfluid flow
03.65.Yz Decoherence; open systems; quantum statistical methods
05.10.Gg Stochastic analysis methods (Fokker-Planck, Langevin, etc.)
81S30 Phase space methods including Wigner distributions, etc.
Quantum gases, liquids and solids
Issue 5 (3 February 2006)
Received 21 June 2005, in final form 28 November 2005
Published 18 January 2006
P Deuar and P D Drummond 2006 J. Phys. A: Math. Gen. 39 1163
Daniel Sigg 2004 Class. Quantum Grav. 21 S409
T Moiseev et al 2009 J. Phys. D: Appl. Phys. 42 072003
T Pierre and G Leclert 1989 Plasma Phys. Control. Fusion 31 371
2008 J. Radiol. Prot. 28
Irving J Bigio and Judith R Mourant 1997 Phys. Med. Biol. 42 803
Li Rui et al 2008 Chinese Phys. Lett. 25 1644
A C Alvarez et al 2006 Inverse Problems 22 69
D H Kobe 1983 J. Phys. A: Math. Gen. 16 737
2000 J. Radiol. Prot. 20 69