Proposal for a Tunable and Switchable Multiwavelength Laser With Variable Spacing Based on Broadband Cascaded Quadratic Nonlinearity

A scheme to realize a tunable and switchable multi-wavelength laser with variable wavelength spacing is proposed based on broadband cascaded quadratic nonlinear interactions in an aperiodically poled MgO-doped lithium niobate (MgO:APPLN) waveguide. Four output wavelengths can be generated simultaneously from the laser and can be switched by tuning the operation temperature of MgO:APPLN. Additionally, the four output wavelengths of the laser can be selected by launching two seeded lights with different wavelengths and wavelength spacing. This device, capable of wavelength tunable function, will facilitate applications in the fiber sensing and wavelength routing for dense wavelength-division-multiplexed (WDM) networks.