Group seminar at LMU and Zoom: The SSH model, 10-fold way SPT classification and band topology in 1D classical system with inversion symmetry

Rongpei Zhu, Chinese University of Hong Kong
Group seminar at LMU seminar room and Zoom
Tuesday, July 18th, 10:00 am (MEZ)

Abstract:

As one of the simplest models, the SSH model describes the topological properties of 1D dimer chain with chiral symmetry. In the 10-fold way symmetry protected topological classification, the SSH model was classified into AIII class, in which only chiral symmetry was maintained while the particle hole symmetry and the time reversal symmetry were lifted. But if the system has a certain external symmetry such as the general inversion symmetry, things would be different. For example, if the system has time reversal symmetry as well as inversion symmetry, the parity properties of the Bloch function at high symmetry points would be enough to distinguish the trivial or non-trivial state. In our case, we considered the 1D classical correspondence of the Berry phase, in which the topological invariant with inversion symmetry would be like a kind of Z2 invariant, and the band topology of the system would be robust against the impact of the local resonance channel.