Circular-polarization-selective perfect reflection in chiral superconductors

Time-reversal-symmetry breaking in quantum materials leads to interesting magnetic and topological phenomena. Chiral superconductivity is one such phenomenon that has gained much attention. The main motivation for its pursuit was the theoretical prediction that Majorana fermions emerge at the edge of chiral superconductors in the topological phase. On the other hand, their non-topological properties, such as optical responses, have not been extensively studied, leaving largely open the question of what kinds of intriguing phenomena might occur. In this talk, we report a theoretical discovery that chiral superconductors can exhibit a novel distinguished optical property that is absent in other phases. Specifically, we show that circular-polarization-selective perfect reflection can occur in chiral superconductors, making them novel single-crystal mirrors with strong time-reversal-symmetry breaking effects. We identify the conditions for the circular-polarization-selective perfect reflection to occur and support our theoretical analysis with model calculations.