Physics – Condensed Matter – Quantum Gases
Scientific paper
2011-08-26
Phys. Rev. Lett. 107, 140401 (2011)
Physics
Condensed Matter
Quantum Gases
5 pages, 6 figures
Scientific paper
10.1103/PhysRevLett.107.140401
In three dimensions, non-interacting bosons undergo Bose-Einstein condensation at a critical temperature, $T_{c}$, which is slightly shifted by $\Delta T_{\mathrm{c}}$, if the particles interact. We calculate the excitation spectrum of interacting Bose-systems, \sup{4}He and \sup{87}Rb, and show that a roton minimum emerges in the spectrum above a threshold value of the gas parameter. We provide a general theoretical argument for why the roton minimum and the maximal upward critical temperature shift are related. We also suggest two experimental avenues to observe rotons in condensates. These results, based upon a Path-Integral Monte-Carlo approach, provide a microscopic explanation of the shift in the critical temperature and also show that a roton minimum does emerge in the excitation spectrum of particles with a structureless, short-range, two-body interaction.
Cormack Samuel C.
Hutchinson David A. W.
Schumayer Dániel
No associations
LandOfFree
Rotons in interacting ultracold Bose gases 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 Rotons in interacting ultracold Bose gases, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Rotons in interacting ultracold Bose gases will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-501675