Competing interactions in dipolar erbium atoms
DIPC Seminars
- Speaker
-
Gabriele Natale, University of Innsbruck, Austria
- When
-
2023/02/10
13:30 - Place
- Donostia International Physics Center
- Add to calendar
- iCal
Ultracold magnetic atoms exhibit short-range contact interactions together
with long-range dipole-dipole interactions. The competition between these two
interactions gives rise to various quantum phases [1], where the usually
dominant mean-field interactions are small and the system is governed by
quantum fluctuations [2].
In this talk, I will first report on the study of a supersolid state and its
excitation spectrum [3]. In such a state, two symmetries are spontaneously
broken: the gauge symmetry, associated with the phase coherence of a
superfluid, and the translational invariance, signalizing crystalline order.
As a result, two distinct branches appear in the excitation spectrum, one for
each broken symmetry. In the second part of the talk, we add a one-dimensional
optical lattice to the system and create a platform, in which quantum
fluctuations are still unexplored and a variety of new phases may be
observable. We employ Bloch oscillations as an interferometric tool to assess
the role that quantum fluctuations play in an array of quasi-two- dimensional
Bose-Einstein condensates [4]. We observe a transition to a state localized
into a single lattice site purely driven by interactions. Finally, we uncover
the parameter regimes where both droplet and soliton states can be achieved.
[1] L. Chomaz, I. Ferrier-Barbut, F. Ferlaino, B. Laburthe- Tolra, B. L. Lev,
and T.Pfau, Dipolar physics: A review of experiments with magnetic quantum
gases. ArXiv: 2201.02672 (2022)
[2] A. R. P. Lima and A. Pelster, Beyond mean-field low- lying excitations of
dipolar Bose gases, Phys.Rev. A 86, 063609 (2012)
[3] G. Natale, R.M.W. van Bijnen, A. Patscheider, D. Petter, M.J. Mark, L.
Chomaz, and F. Ferlaino, Excitation Spectrum of a Trapped Dipolar Supersolid
and Its Experimental Evidence, Phys. Rev. Lett. 123, 050402 (2019)
[4] G. Natale, T. Bland, S. Gschwendtner, L. Lafforgue, D. S. Grun, A.
Patscheider, M. J. Mark and F. Ferlaino, Bloch oscillations and matter-wave
localization of a dipolar quantum gas in a one dimensional lattice, Comm.
Phys. 5, 227 (2022)
Host: Ricardo Diez Muino
Zoom:
Note: This lecture is part of the joint session with talk by Claudia Politi
scheduled at 12:00 p.m.