Dartmouth Events

Physics & Astronomy Quantum Nano Seminar - Abhijeet Alase, Dartmouth College

Title: "Investigation of Topological Edge States Using Generalized Bloch Theorem"

Thursday, March 29, 2018
4:00pm – 5:00pm
Wilder 202
Intended Audience(s): Public
Categories: Lectures & Seminars

Abstract: The non-trivial topology of the bulk of topological insulators and superconductors manifests in the form of edge states protected by discrete symmetries - a principle known as the "bulk-edge correspondence". While our understanding of such protected states has so far largely relied on the analysis of the bulk topological properties, a main drawback of this approach is that it provides little (if any) information about the wavefunctions of the protected states, as well as their response to symmetry-breaking perturbations. We present a generalization of Bloch's theorem able to accommodate the effects of terminations and interfaces modeled by effective boundary conditions, leading to an exact algebraic solution for all energy eigenstates and eigenvalues. Using our approach, we compute analytically the energies and wavefunctions of Andreev bound states supported on the metallic link in a one-dimensional SNS junction. We also show that the penetration depth of the chiral edge states of p+ip superconductor on a lattice diverges near those points in the surface Brillouin zone where the edge bands touch the bulk bands.
 

For more information, contact:
Tressena Manning
603-646-2854

Events are free and open to the public unless otherwise noted.