Fig. 1. Schematic structures of (a) the TDM interleavers in parallel and serial configurations, (b) the WDM interleaver, and (c) the MDM interleaver.

Fig. 2. (a) Schematic structure of a wavelength-mode interleaved photonic signal processing system. (b) The structure of the wavelength demultiplexer based on two-stage cascaded Mach–Zehnder interferometers. (c) The structure of the mode converter and multiplexer.

Fig. 3. (a) Optical microscope image of the fabricated chip. (b) A photo of the packaged chip with fiber array coupling and electrical wire-bonding to a PCB.

Fig. 4. (a) The transmission spectra of the 1×4 wavelength demultiplexer. (b) The transmission spectrum of the wavelength-division interleaver. (c) (left) The optical pulse waveforms at the end of the wavelength-division interleaver. (right) The delay error of the optical pulses. The red color indicates the measured pulses and the green color indicates the ideal pulses with a time interval of 250 ps.

Fig. 5. (a) The transmission spectra from output ports O1,1, O1,2, O1,3, and O1,4 through TE1 mode transmission in the multimode waveguide. (b) The transmission spectra from output ports O2,1, O2,2, O2,3, and O2,4 through TE3 mode transmission in the multimode waveguide. (c) (left) The optical pulse waveforms at the end of the wavelength-mode-division interleaver. Dotted curves: the optical pulse through the TE1 mode; solid curves: the optical pulse through the TE3 mode. (right) The delay error of the optical pulses. The red color indicates the measured pulses and the green color indicates the ideal pulses with a time interval of 125 ps.