Amnon Aharony: Non-symmetric diamond chains with magnetic and electrical fields

Title: Non-symmetric diamond chains with magnetic and electrical fields: at bands, edge states and topology

Abstract: he diamond chain is solved with the Aharonov-Bohm (AB) caging, spin-orbit interactions [Aharonov-Casher (AC) caging], Zeeman magnetic fields and Su-Schrieffer-Heeger (SSH) bonds. Limits of the latter yield spin-dependent decoupled trimers. Some symmetric limits yield flat bands, with spin-dependent compact localized states spanning two unit cells (diamonds). Asymmetries and Zeeman fields turn the flat bands into pairs of narrow dispersive bands, with potential full spin filtering. Finite chains yield topological edge states, in a range which is enhanced by AB and AC caging. The outlook contains scattering from finite chains and calculation of the Zak phases.