Physics – Condensed Matter – Mesoscale and Nanoscale Physics
Scientific paper
2009-03-14
Phys. Rev. A 79, 063633 (2009)
Physics
Condensed Matter
Mesoscale and Nanoscale Physics
9 pages, 8 figures
Scientific paper
10.1103/PhysRevA.79.063633
Using a Luttinger-liquid approach we study the quantum fluctuations of a Bose-Josephson junction, consisting of a Bose gas confined to a quasi one-dimensional ring trap which contains a localized repulsive potential barrier. For an infinite barrier we study the one-particle and two-particle static correlation functions. For the one-body density-matrix we obtain different power-law decays depending on the location of the probe points with respect to the position of the barrier. This quasi-long range order can be experimentally probed in principle using an interference measurement. The corresponding momentum distribution at small momenta is also shown to be affected by the presence of the barrier and to display the universal power-law behavior expected for an interacting 1D fluid. We also evaluate the particle density profile, and by comparing with the exact results in the Tonks-Girardeau limit we fix the nonuniversal parameters of the Luttinger-liquid theory. Once the parameters are determined from one-body properties, we evaluate the density-density correlation function, finding a remarkable agreement between the Luttinger liquid predictions and the exact result in the Tonks-Girardeau limit, even at the length scale of the Friedel-like oscillations which characterize the behavior of the density-density correlation function at intermediate distance. Finally, for a large but finite barrier we use the one-body correlation function to estimate the effect of quantum fluctuations on the renormalization of the barrier height, finding a reduction of the effective Josephson coupling energy, which depends on the length of the ring and on the interaction strength.
Didier Nicolas
Hekking Frank W. J.
Minguzzi Anna
No associations
LandOfFree
Quantum fluctuations of a Bose-Josephson junction in a quasi-one-dimensional ring trap does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Quantum fluctuations of a Bose-Josephson junction in a quasi-one-dimensional ring trap, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quantum fluctuations of a Bose-Josephson junction in a quasi-one-dimensional ring trap will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-236018