Fig. 1. (a) Schematic of the proposed switch matrix. (b) Zoom-in view of a single mesh cell. (c) Cross-sectional view of the MDR along the red dashed line in (b).

Fig. 2. Simulated temperature distributions in the core region of (a) the conventional mesh cells with two MDRs and (b) the proposed mesh cells with two MDRs and routing waveguides designed to maintain a 250 μm spacing between them. An electric power of 25 mW is applied to the TiN micro-heater on top of MDR1. (c), (d) Simulated transmission spectra at the drop ports of the two MDRs in the mesh cells, as illustrated in (a) and (b), respectively, when the electric power applied to the micro-heater on top of the MDR1 is 0 and 25 mW.

Fig. 3. (a) Schematic of the 1×8×2λ switch matrix. (b) Microphotograph of the fabricated 1×8 switch matrix chip. The insets show the zoom-in views of the MDR and the waveguide crossing. (c) Photograph of the wire-bonded chip. The inset provides the zoom-in view of the photonic chip area, including the fabricated chip, the wire bonding, and the fiber array.

Fig. 4. (a) Measured transmission spectra at the output ports O0 to O8 of the switch matrix in the static state. (b) Wavelength tuning of the MDR with the power applied to the micro-heater on top of the MDR increasing.

Fig. 5. Switching time of the fabricated switch matrix.

Fig. 6. (a) Measured on-off transmission responses of the channel from I0 to O2. (b) Measured transmission spectra of all channels when the MDR in the channel from I0 to O2 is switched on. (c) Measured on-off ER and channel crosstalk of all eight channels.

Fig. 7. Measured resonance wavelength shifts of each MDR (a) in the conventional mesh cell and (b) in the proposed mesh cell when the power consumption on micro-heaters on top of MDR1 increases.

Fig. 8. (a) Experimental setup for data transmission. (b) Measured eye diagrams for each channel of the switch chip as well as for the B2B operation.

Fig. 9. (a) Measured transmission spectra of the routing channel from I0 to O1 and from I0 to O4. (b) Optical spectra of the modulated signals before coupling into the switch. (c) Measured spectra of the modulated optical signal at output port O1 after EDFA amplification. (d) Output spectra of the modulated optical signal at output port O4 after EDFA amplification. (e) Eye diagrams of the received signals at 15 Gbps and 20 Gbps under B2B, single-wavelength-channel routing, and dual-wavelength-channel routing conditions.