Switchable pulse and multi-wavelength laser based on non-linear polarization rotation

A nonlinear polarization rotation (NPR) based Erbium doped fiber laser (EDFL) with dual functions laser characteristic is demonstrated using a highly concentrated Erbium doped fiber (EDF). When the polarization of light is subjected to the appropriate polarization, the EDFL can function as a soliton pulse laser or multi-wavelength laser. The intensity dependent transmission or loss determines the operation state of laser. When the EDFL operates as a soliton pulse laser, it exhibits repetition rate at 6.25 MHz with pulse width of 1.06 ps. When the EDFL operates as a multi-wavelength laser, it has 3 distinct lasing wavelengths evenly spaced at 1.7 nm.