Ultracold atoms in optical quasicrystals: Localization, Fractal Structures and Synthetic Dimensions

Add to your list(s) Download to your calendar using vCal

• Ulrich Schneider (Cambridge)
• Thursday 06 February 2020, 13:15-14:45
• Theory Library.

If you have a question about this talk, please contact Dr Hannah Price.

Note the new time for Theory seminars this term

Quasicrystals are a novel form of condensed matter that is not periodic, but nonetheless long-range ordered. Similar to periodic crystals, quasicrystals give rise to diffraction patterns consisting of sharp Bragg peaks—but with rotational symmetries forbidden for periodic structures. They can be described by self-similar, fractal tilings containing more than one type of unit cell, such as the celebrated Penrose tiling. Many foundational concepts of periodic systems such as Blochwaves or Brillouin zones are not applicable to quasicrystals, thereby giving rise to new physics. Examples include many-body localization, phasonic degrees of freedom, fractal band structures, and a direct link to higher dimensions via cut-and-project techniques, where quasicrystals can inherit topological properties from their periodic parents. In this talk, I will present our experimental realization of an eightfold symmetric optical quasicrystal for ultracold atoms. Matter-wave diffraction directly reveals the self-similar fractal nature of this potential and realizes quantum walks in up to four synthetic dimensions. I will also present the localization transition in these potentials and close by discussing the prospect for the 2D Bose glass and Many-body localization in these potentials.

This talk is part of the Theoretical Physics Seminars series.

This talk is included in these lists:

• Bham Talks
• Theoretical Physics Seminars
• Theory Library
• What's on in Physics?

Note that ex-directory lists are not shown.