Nonlinear coherent perfect photon absorber in asymmetrical atom–nanowires coupling system**Project supported by the National Natural Science Foundation of China (Grant Nos. 11864018 and 11574229), Scientific Research Foundation of the Education Department of Jiangxi Province of China (Grant No. GJJ170645), and Doctor Startup Fund of the Natural Science of Jinggangshan University, China (Grant No. JZB16003).

Abstract

Coherent perfect absorption provides a method of light-controlling-light and has practical applications in optical communications. Recently, a cavity-based nonlinear perfect photon absorption extends the coherent perfect absorber (CPA) beyond the linear regime. As nanowire-based system is a more competitive candidate for full-optical device, we introduce a nonlinear CPA in the single two-level atom–nanowires coupling system in this work. Nonlinear input–output relations are derived analytically, and three contributions of atomic saturation nonlinearity are explicit. The consociation of optical nonlinearity and destructive interference makes it feasible to fabricate a nonlinear monoatomic CPA. Our results also indicate that a nonlinear system may work linearly even when the incoming lights are not weak any more. Our findings show promising applications in full-optical devices.