Ultrashort fractional transform solutions for wave propagation in inhomogeneous twin-core optical waveguides

We study the propagation of ultrashort-pulses in asymmetric twin-core optical waveguide represented by the variable-coefficient higher-order nonlinear Schrödinger equation with complex potential and source term. We investigate the presence of localized as well as periodic solutions using self-similarity transformation and fractional transformation technique. Dynamical evolution of these solutions is studied through the judicious choice of tapering profile and source parameter. Our exact analysis helps us to identify the inhomogeneous waveguide to satisfy the PT-symmetric property.