Topological control of the nonlinear-optical response of hybrid quantum systems

Abstract

We map the topological properties of a one dimensional superlattice to the optical properties of an electronic system. We find that the nonlinear-optical response is optimized for electrons that live in the transitional morphology between topologically protected edge states and delocalized eigenstates. This provides a novel means of tuning the nonlinear-optical response of hybrid quantum systems. We show how these characteristics can be used to mimic saturable absorption and illustrate how 'quantum cords' can be used to build an efficient all-optical switch. ONE DIMENSIONAL SUPERLATTICE AND TOPOLOGICAL EDGE STATESA superlattice in 1+1 dimensions is defined as a one dimensional lattice with a virtual second dimension. Examples of this include the Fermi-Hubbard model with modulated on-site energy [21], the Kronig-Penny model with arbitrary scatters [22], and non-interacting trigonometric potentials. [23] In