Fig. 1. (a) Schematic diagram of the proposed device. Enlarged view for (b) the asymmetric Y-junction and (c) the MMI coupler. (d) Cross-section for the modulation region.

Fig. 2. (a) Thermal field distribution of the device when Heater-1 is turned on. (b) Simulated transmission of the E11, E12, E21, and E22 modes as a function of ΔT1. (c) Simulated transmission spectra of the E11, E12, E21, and E22 modes as a function of the wavelength. (d) Simulated propagation results at 1550 nm wavelength for each mode individually.

Fig. 3. (a) Thermal field distribution of the device when Heater-2 is on. (b) Simulated transmission of the E11, E12, E21, and E22 modes as a function of ΔT2. (c) Thermal field distribution of the device when Heater-3 is on. (b) Simulated transmission of the E11, E12, E21, and E22 modes as a function of ΔT3.

Fig. 4. (a) Steps in the fabrication of the proposed MWOS with polymer materials. The top-view microscope images of (b) the asymmetric Y-junction and (c) the MMI couplers. Microscope images of (d) the electrode heater and (e) an end face of the fabricated device.

Fig. 5. (a) Measured transmission of the E11, E12, E21, and E22 modes as a function of P1. (b) Measured transmission spectra of the E11, E12, E21, and E22 modes as a function of the wavelength. (c) Output near-field photos with different P1 when E11, E12, E21, or E22 mode was launched into the device at the 1550 nm wavelength.

Fig. 6. (a) Measured transmission of the E11, E12, E21, and E22 modes as a function of P2. (b) Output near-field photos with different P2 when the E11, E12, E21, or E22 modes were launched into the device at the 1550 nm wavelength. (c) Measured transmission of the E11, E12, E21 and E22 modes as a function of P3. (d) Output near-field photos with different P3 when E11, E12, E21, or E22 mode was launched into the device at the 1550 nm wavelength.

Fig. 7. Measured dynamic switching of the proposed MWOS when the (a) E11, (b) E12, (c) E21, and (d) E22 modes were launched into the device.

Fig. 8. Schematic structure of an eight-mode multifunctional switch.