Our new ERC project on creating an Optical Quasicrystal has started on January 1st. The main objective of this project is to extend the level of control achieved in optical lattices to 2D quasiperiodic potentials by realising an optical quasicrystal.
Quasicrystals are a novel form of condensed matter that is non-periodic, but long-range ordered. They have first been observed in the 1980s by Dan Shechtman in diffraction experiments. Quasicrystals give rise to a pattern of sharp Bragg peaks, similar to periodic crystals, but with rotational symmetries that are impossible for periodic structures. Their structure was found to be related to aperiodic tilings with more than one unit cell, such as the celebrated Penrose tiling.
Even though quasicrystals are long-range ordered, many foundational concepts of periodic condensed matter systems such as Blochwaves or Brillouin zones are not applicable. This places them on an interesting middle ground between periodic and disordered systems and highlights their potential for novel many-body physics. We will look for interesting novel phases and investigate the topological properties of quasiperiodic potentials as well as study their transport properties and out-of-equilibrium dynamics.
We plan build a versatile quantum simulator for the physics of quasicrystals by combining a non-periodic optical potential with ultracold Rubidium and Potassium gases.