Performance analysis of Ti∶ LiNbO3 1×2 digital photonic switch with SiO2 buffer layer

Abstract

We demonstrate a polarization and wavelength independent digital photonic switch with optimized on-chip area coverage and reduced driving voltage. A symmetrical SiO2 buffer layer was introduced between channel and electrode regions to optimize its thermal stability and to reduce absorption losses. Switching is achieved through adiabatic mode evolution in an asymmetric waveguide junction. The switch has been found satisfactory for THz operation with switching voltages in the range of ±18-to-21V and switch losses in the range of 0.50 to 0.75% only. A channel profile of titanium indiffused waveguide on an x-cut lithium niobate substrate is used for lightwave propagation.