Bridging topological physics and quantum photonics

Sunil Mittal (Hosted by Murch), University of Maryland, Joint Quantum Institute / IREAP

A deeper understanding of the role of topology in condensed matter physics has led to a new paradigm of topological phases of matter, for example, the topological insulators. While insulating in their bulk, these systems host conducting states at their boundaries that are chiral and, therefore, robust against disorders. Spurred by this chirality and robustness, photonic systems have recently emerged as an attractive platform for simulations of various condensed matter topological model systems, for example, the integer quantum Hall effect. Photonic simulations allow for investigations of exotic topological models that are either challenging for fermionic systems or unique to bosonic systems. At the same time, topological features such as chirality provide a novel and robust route to manipulate the photonic mode structure and quantum photonic processes. 

In this talk I will present two examples of such synergy between topological physics and quantum photonics. First, I will present a topological source of quantum light where topological boundary states are used for robust manipulations of the quantum correlations between generated photons. Second, I will present a photonic realization of the quadrupole topological phases that belong to the recently discovered category of higher-order topological insulators. Finally, I will discuss the prospects of generating novel topological phases and quantum states of light.