Numerical and Experimental Study on Pulse Propagation with Coupling Loss in Nonlinear Chiral Fiber Couplers

Abstract

In this research, we present a more general theory to describe the propagation of beams through chiral nonlinear fiber couplers. Considering Post’s constitutive relations and Maxwell’s equations, we derive the generalized coupled chiral nonlinear Schrödinger equations (CCNLSEs). The CCNLSEs govern the evolution of left- and right-handed circularly polarized (LCP and RCP) components with joint action of chirality, dispersion, and nonlinearity. Using the Runge Kutta method, the linear behavior for low powercontinuous wave (CW) and the characteristics of nonli near switching for high power CWin the couplers are explored The interesting role of chirality in regulating the behavior ofthe different components in the coupl er is demonstrated in our simulation. We found thatthe chirality could provide an additiona l degree of freedom which may find applicationsin design of such a kind of device used in optical communication and remote sensing. W ehave also studied the nonlinear switching characteristics directional fiber couplers experimentally.