Phys.org August 19, 2019 Researchers at Purdue University have developed a unified perspective of unidirectional topological edge waves in nonreciprocal media. They focused on the inherent role of photonic spin in nonreciprocal gyroelectric media, i.e. magnetized metals or magnetized insulators. Hamiltonian approach predicts the existence of a third distinct class of Maxwellian edge wave exhibiting topological protection. This occurs in an intriguing topological bosonic phase of matter, fundamentally different from any known electronic or photonic medium. The goal of their paper is to discuss the three foundational classes of edge waves in a unified perspective while providing in-depth derivations, taking […]