Observation of Switching Phenomena in Non-ether PPQ Planar Waveguide with Two-wavelength Nonlinear Prism Coupling

In the past two decades, third-order nonlinear optical properties of organic and polymeric materials have attracted considerable attention to realize all-optical signal processing devices.1,2 Especially, the large off-resonance third-order optical nonlinearities of conjugated organic polymers with delocalized π--electron systems, such as polydiacetylenes3,4, are considered to be potential candidates. Although conjugated polymer is reported to have large χ(3) and fast response time, many of them are highly intractable materials that are difficult to process to form the low-loss waveguide structures required for their application5. Recently, many techniques for fabricating low-loss planar waveguides in thin films of solution processible conjugated polymer have been developed7,8 besides third-order nonlinear optical polymers that exhibit low absorption have been reported6 Furthermore, numerous different schemes which aim is all-optical switching and all-optical logic operations have been suggested for practical devices. They are included in nonlinear prism and grating couplers and nonlinear directional couplers9,10, such as two-channel nonlinear directional couplers, nonlinear Mach-Zehnder interferometers, nonlinear distributed-feedback grating reflectors and adiabatic polymer-glass-waveguide all-optical switch11,12. However, though the prism coupler has attracted partially significant attention both theoretically13 and experimentally14, as so far we know the nonlinear prism coupling to organic polymer waveguide has only been demonstrated in single beam experiments on intense-dependent nonlinear effects15.