Boundary Physics and Bulk-Boundary Correspondence in Topological Phases of Matter

Description

This thesis extends our understanding of systems of independent electrons by developing a generalization of Bloch’s Theorem which is applicable whenever translational symmetry is broken solely due to arbitrary boundary conditions. The thesis begins with a historical overview of topological condensed matter physics, placing the work in context, before introducing the generalized form of Bloch's Theorem. A cornerstone of electronic band structure and transport theory in crystalline matter, Bloch's Theorem is generalized via a reformulation of the diagonalization problem in terms of corner-modified block-Toeplitz matrices and, physically, by allowing the crystal momentum to take complex values. This formulation provides exact expressions for all the energy eigenvalues and eigenstates of the single-particle Hamiltonian. By precisely capturing the interplay between bulk and boundary properties, this affords an exact analysis of several prototypical models relevant to symmetry-protected topological phases of matter, including a characterization of zero-energy localized boundary excitations in both topological insulators and superconductors. Notably, in combination with suitable matrix factorization techniques, the generalized Bloch Hamiltonian is also shown to provide a natural starting point for a unified derivation of bulk-boundary correspondence for all symmetry classes in one dimension. Front Matter ....Pages i-xvii Introduction (Abhijeet Alase)....Pages 1-12 Generalization of Bloch’s Theorem to Systems with Boundary (Abhijeet Alase)....Pages 13-63 Investigation of Topological Boundary States via Generalized Bloch Theorem (Abhijeet Alase)....Pages 65-122 Matrix Factorization Approach to Bulk-Boundary Correspondence (Abhijeet Alase)....Pages 123-157 Mathematical Foundations to the Generalized Bloch Theorem (Abhijeet Alase)....Pages 159-190 Summary and Outlook (Abhijeet Alase)....Pages 191-198 Back Matter ....Pages 199-200