2020/01/29 by Matteo Sbroscia, Konrad Viebahn, Edward Carter +3 · 2 citations
Physics and Astronomy · #cond-mat.quant-gas #cond-mat.dis-nn #cond-mat.stat-mech #cond-mat.str-el #quant-ph
paper · pdf · doi:10.1103/physrevlett.125.200604
published as Phys. Rev. Lett. 125, 200604 (2020)
arxiv created 2020/01/29 · arxiv updated 2020/12/02
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 V0=1.78(2) Erec 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.