Lancaster EPrints

Partial chiral symmetry-breaking as a route to spectrally isolated topological defect states in two-dimensional artificial materials

Poli, Charles Joseph and Schomerus, Henning Ulrich and Bellec, Matthieu and Kuhl, Ulrich and Mortessagne, Fabrice (2017) Partial chiral symmetry-breaking as a route to spectrally isolated topological defect states in two-dimensional artificial materials. 2D Materials, 4 (2). ISSN 2053-1583

[img] PDF (Poli_2017_2D_Mater._4_025008) - Published Version
Available under License Creative Commons Attribution.

Download (1915Kb)
    [img]
    Preview
    PDF (paper) - Submitted Version
    Download (11Mb) | Preview

      Abstract

      Bipartite quantum systems from the chiral universality classes admit topologically protected zero modes at point defects. However, in two-dimensional systems these states can be difficult to separate from compacton-like localized states that arise from flat bands, formed if the two sublattices support a different number of sites within a unit cell. Here we identify a natural reduction of chiral symmetry, obtained by coupling sites on the majority sublattice, which gives rise to spectrally isolated point-defect states, topologically characterized as zero modes supported by the complementary minority sublattice. We observe these states in a microwave realization of a dimerized Lieb lattice with next-nearest neighbour coupling, and also demonstrate topological mode selection via sublattice-staggered absorption.

      Item Type: Journal Article
      Journal or Publication Title: 2D Materials
      Uncontrolled Keywords: defect states ; topological materials ; symmetries ; mode selection ; flat bands ; Lieb lattice ; Dirac points
      Subjects:
      Departments: Faculty of Science and Technology > Physics
      ID Code: 84367
      Deposited By: ep_importer_pure
      Deposited On: 26 Jan 2017 11:52
      Refereed?: Yes
      Published?: Published
      Last Modified: 20 Jul 2018 01:05
      Identification Number:
      URI: http://eprints.lancs.ac.uk/id/eprint/84367

      Actions (login required)

      View Item