Topological Origin of Zero-Energy Edge States in Particle-Hole Symmetric Systems

Shinsei Ryu; Yasuhiro Hatsugai

doi:10.1103/physrevlett.89.077002

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Topological Origin of Zero-Energy Edge States in Particle-Hole Symmetric Systems

Shinsei Ryu·Yasuhiro Hatsugai

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Abstract

A criterion to determine the existence of zero-energy edge states is discussed for a class of particle-hole symmetric Hamiltonians. A ``loop'' in a parameter space is assigned for each one-dimensional bulk Hamiltonian, and its topological properties, combined with the chiral symmetry, play an essential role. It provides a unified framework to discuss zero-energy edge modes for several systems such as fully gapped superconductors, two-dimensional d-wave superconductors, and graphite ribbons. A variants of the Peierls instability caused by the presence of edges is also discussed.

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Shinsei Ryu, Yasuhiro Hatsugai. 2002-08-06. Topological Origin of Zero-Energy Edge States in Particle-Hole Symmetric Systems. https://doi.org/10.1103/physrevlett.89.077002

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