A novel "cascaded" waveguide phasematching arrangement

Summary form only given. Compound III-V semiconductors, such as GaAs and GaP have high nonlinear coefficient d/sub 36/ of the order of 100 pm/V or more, but, unfortunately, these materials are not widely used for nonlinear frequency conversion since they are neither birefringent nor ferroelectric, i.e. III-V materials cannot be phasematched by the angle tuning while the quasi-phasematching (QPM) can be achieved only by a complicated process of wafer bonding followed by overgrowth. We have proposed a new simple method of phasematching in nonlinear waveguides and estimated its efficiency.