Fig. 1. Schematic illustration of our proposed multidimensional optical multicasting scheme. (a) Multicast chip consists of mode multiplexers and a multi-mode PIN silicon waveguide. The PIN junction enhances the nonlinearity efficiency of the waveguide, thus enabling the replication of the signal light from one initial frequency to nine divergent frequencies and from one starting mode to two separate modes. (b) Spectrum of output light. P1, P2, and P3 correspond to the pump lights, and Is denotes the signal light. Multicast lights (MCs) are denoted as MC1–MC9. The table lists the frequencies of these multicast lights. (c) Cross-section of the multi-mode PIN silicon waveguide. The right side of the figure shows the mode field distributions of different modes within the waveguide.

Fig. 2. (a) The variation of the waveguide’s nonlinearity coefficient and loss with waveguide width. (b) The variation of the waveguide’s normalized conversion efficiency with waveguide length.

Fig. 3. The experiment setup and result of testing nonlinearity enhancement of silicon waveguide with reverse-biased PIN junctions. (a) The experiment setup of testing nonlinearity enhancement of multi-mode PIN silicon waveguide. EDFA, erbium-doped fiber amplifier; OSA, optical spectrum analyzer. (b) Power of output idler light versus reverse bias voltage; different curves represent different pump powers. (c) Spectrum of the output light in TE0 mode. (d) Conversion efficiency versus the wavelength of probe light in TE0 mode. (e) Transmission spectra for different ports.

Fig. 4. (a) The experiment setup of 80 Gb/s QPSK wavelength multicasting in three modes. WDM, wavelength division multiplexer; TBPF, tunable bandpass filter; ATT, attenuator; OMA, optical modulation analyzer. (b) Spectrum of input light. P1, P2, and P3 are three coherent pump lights filtered from the Kerr frequency comb, and Is is an 80 Gb/s QPSK signal.

Fig. 5. The experiment result of 80 Gb/s QPSK wavelength multicasting in three modes. (a)–(c) Spectrum of output light of TE0, TE1, TE2 modes; the inset is the constellation diagram of each replica. (d) EVM of the replicas and original signal of TE0 (circle), TE1 (inverted triangle), and TE2 (triangle) modes.

Fig. 6. (a) The BER curves of replicas and original signal of TE0 mode; different curves correspond to different channels. (b) The BER curves of replicas and original signal of TE1 mode.

Fig. 7. The experiment result of simultaneous 80 Gb/s QPSK multicasting of two modes in 14 channels. (a) EVM and constellation diagram of each replica and original signal of TE0 (circle) and TE1 (inverted triangle) modes. (b) BER of replicas and original signal of TE0 (circle) and TE1 (inverted triangle) modes.

Fig. 8. Schematic diagram of our proposed multidimensional optical multicasting applied in optical computing to improve computing power by increasing the number of channels. MMC, multidimensional multicast chip; MDM, mode-division multiplexer.