Efficient All-Optical Transistor Action in Short-Length Multimode Optical Fibers

Abstract

The quest for realizing an all-optical transistor while fulfilling desired criteria has been around since long time. Various schemes have been put forward over the years to achieve it; however, almost all techniques make use of at least two different laser sources. Optical event horizon principle has also been employed to see transistor action in glass fibers using two different frequency sources. In this paper, we report an optical transistor action in short-length, tailor-made multimode optical fibers through a single pump only. The higher order mode properties of the fiber and intermodal nonlinear interaction (mainly cross-phase modulation) are used to achieve efficient transistor action. Both the soliton and a weak dispersive pulse are excited in $ LP_{02}$ and $ LP_{01}$ modes of the fiber, respectively, with a certain temporal delay set by the sign of the differential group delay between the modes. We believe that the scheme has potential to improve system performance owing to the fact that only a single-wavelength pump source is required as opposed to the optical-transistor devices available till date that essentially require two-color pumping.