# Condensed Matter Seminar: "Photonic analogues of topological superconductors"

#### Thursday, November 16, 2017 - 11:30am

Interest continues to grow in photonic analogues of topological electronic phases. In most cases, these systems are non-interacting, and have the same band structure and edge state structure as their fermionic counterparts. In this talk, I'll discuss recent theory work in my group showing how parametric "two-photon" driving can be used to realize a new class of photonic topological systems that superficially resemble topological superconductors. Unlike standard particle-number conserving models of non-interacting topological phases, these new systems exhibit crucial differences between their bosonic and fermionic versions. Further, one can realize a situation where all bulk states are stable, but where edge states are guaranteed to be unstable. Such a system can form the basis of a useful device: a topologically-protected amplifier which operates close to the fundamental limits set by quantum mechanics. I'll discuss how these ideas could be realized in a variety of different experimental platforms, including superconducting quantum circuits and optomechanics.