Odd waveguide mode quasi-phase-matching using angled gratings

Summary from only given. An approach for quasi-phase-matching (QPM) is to use odd and even waveguide modes for the interacting waves; these modes can be filtered or separated with integrated optical components. Although QPM usually involves the fundamental modes of the interacting wavelengths in waveguide nonlinear optics, the technique can also be applied to mixing involving higher-order modes, as demonstrated here.