Physics – Condensed Matter – Mesoscale and Nanoscale Physics
Scientific paper
2005-12-26
Physics
Condensed Matter
Mesoscale and Nanoscale Physics
13 pages, 3 figures
Scientific paper
10.1103/PhysRevB.73.235352
The superfluid phase transition of bosons in a two-dimensional (2D) system with disorder and an external parabolic potential is studied. The theory is applied to experiments on indirect excitons in coupled quantum wells. The random field is allowed to be large compared to the dipole-dipole repulsion between excitons. The slope of the external parabolic trap is assumed to change slowly enough to apply the local density approximation (LDA) for the superfluid density, which allows us to calculate the Kosterlitz-Thouless temperature $T_{c}(n(r))$ at each local point $r$ of the trap. The superfluid phase occurs around the center of the trap ($\mathbf{r}=0$) with the normal phase outside this area. As temperature increases, the superfluid area shrinks and disappears at temperature $T_{c}(n(r=0))$. Disorder acts to deplete the condensate; the minimal total number of excitons for which superfluidity exists increases with disorder at fixed temperature. If the disorder is large enough, it can destroy the superfluid entirely. The effect of magnetic field is also calculated for the case of indirect excitons. In a strong magnetic field $H$, the superfluid component decreases, primarily due to the change of the exciton effective mass.
Berman Oleg L.
Coalson Rob D.
Lozovik Yurii E.
Snoke David W.
No associations
LandOfFree
Superfluidity of "dirty" indirect excitons and magnetoexcitons in two-dimensional 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 Superfluidity of "dirty" indirect excitons and magnetoexcitons in two-dimensional trap, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Superfluidity of "dirty" indirect excitons and magnetoexcitons in two-dimensional trap will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-36737