Print Email Facebook Twitter Amorphous topological phases protected by continuous rotation symmetry Title Amorphous topological phases protected by continuous rotation symmetry Author Spring, H. (TU Delft QN/Akhmerov Group; Kavli institute of nanoscience Delft) Akhmerov, A.R. (TU Delft QN/Akhmerov Group; Kavli institute of nanoscience Delft) Varjas, D. (TU Delft QRD/Kouwenhoven Lab; TU Delft QuTech Advanced Research Centre; Kavli institute of nanoscience Delft; Stockholm University) Date 2021 Abstract Protection of topological surface states by reflection symmetry breaks down when the boundary of the sample is misaligned with one of the high symmetry planes of the crystal. We demonstrate that this limitation is removed in amorphous topological materials, where the Hamiltonian is invariant on average under reflection over any axis due to continuous rotation symmetry. We show that the edge remains protected from localization in the topological phase, and the local disorder caused by the amorphous structure results in critical scaling of the transport in the system. In order to classify such phases we perform a systematic search over all the possible symmetry classes in two dimensions and construct the example models realizing each of the proposed topological phases. Finally, we compute the topological invariant of these phases as an integral along a meridian of the spherical Brillouin zone of an amorphous Hamiltonian. To reference this document use: http://resolver.tudelft.nl/uuid:24ecd539-c633-4222-9d9f-f38a0d99502a DOI https://doi.org/10.21468/SCIPOSTPHYS.11.2.022 ISSN 2542-4653 Source SciPost Physics, 11 (2) Part of collection Institutional Repository Document type journal article Rights © 2021 H. Spring, A.R. Akhmerov, D. Varjas Files PDF SciPostPhys_11_2_022.pdf 2.88 MB Close viewer /islandora/object/uuid:24ecd539-c633-4222-9d9f-f38a0d99502a/datastream/OBJ/view