Observing localisation in a 2D quasicrystalline optical lattice
Abstract
Quasicrystals are long-range ordered but not periodic, representing an interesting middle ground between order and disorder. We experimentally and numerically study the ground state of non- and weakly-interacting bosons in an eightfold symmetric quasicrystalline optical lattice. We find extended states for weak lattices but observe a localisation transition at a lattice depth of for the non-interacting system. We identify this transition by measuring the timescale required for adiabatic loading into the lattice, which diverges at the critical lattice depth for localisation. Gross-Pitaevskii simulations show that in interacting systems the transition is shifted to deeper lattices, as expected from superfluid order counteracting localisation. Our experimental results are consistent with such a mean-field shift. Quasiperiodic potentials, lacking conventional rare regions, provide the ideal testing ground to realise many-body localisation in 2D.
Cite
@article{arxiv.2001.10912,
title = {Observing localisation in a 2D quasicrystalline optical lattice},
author = {Matteo Sbroscia and Konrad Viebahn and Edward Carter and Jr-Chiun Yu and Alexander Gaunt and Ulrich Schneider},
journal= {arXiv preprint arXiv:2001.10912},
year = {2020}
}