Mathematical and Physical Aspects of Topologically Protected States

Topological photonics and phononics based on momentum bias and nonlinearities

Andrea Alu

University of Texas at Austin


In this talk, we review our recent progress towards the concept, design and realization of magnet-free non-reciprocal photonic and acoustic devices and arrays of them with strong topological protection, aimed at realizing reconfigurable, broadband isolators, gyrators and circulators. We will discuss our approaches to design topological metasurfaces based on spatio-temporal modulation, nonlinearities, and/or opto-mechanical interactions, and discuss our vision towards new transport phenomena for light and sound, and new devices with enhanced non-reciprocal properties.