All-optical switching in MIM waveguide resonator with an outer portion smooth bend structure containing nonlinear optical materials

All-optical switching based on metal-insulator-metal (MIM) waveguide resonator with an outer portion smooth bend structure containing Kerr nonlinear materials has been proposed and numerically investigated. In our structure, we let pump light locate at mixed-modes (the dips overlap), and then keep strong resonance in the resonator which is helpful for the enhancement of nonlinear effect. Signal light locates at split modes, which makes the full width at half-maximum (FWHM) of dips significantly decrease, and increase the difference of signal light transmittance consequently when pump light is on or off. With the finite-difference time-domain (FDTD) simulations, it is demonstrated that a tiny optical bistability (owing to small detuning parameter which is only 1.143) of the signal light appears by varying the control-light intensity, and the switching time is at approximately the picosecond level.