All-Optical Cross-Absorption-Modulation Based Gb/s Switching With Silicon Quantum Dots

作者：Huang Bo Ji; Wu Chung Lun; Cheng Chih Hsien; Hsieh Cheng Hsuan; Syu Shih Chang; Lin Yung Hsiang; Wang Huai Yung; Tsai Cheng Ting; Chi Yu Chieh; Chang Po Han; Wu Chih I; Lin Gong Ru^*

来源：IEEE Journal of Selected Topics in Quantum Electronics, 2016, 22(6): 1900313.

DOI：10.1109/JSTQE.2016.2553458

• Cross-absorption-modulation
• silicon carbide waveguide
• Si quantum dots

In silicon quantum dots (Si-QDs), the sub-bandgap cross-absorption-modulation (XAM) has been preliminarily observed and confirmed as a new kind of wavelength conversion process to enable ultrafast optical switching. By using the Si-QD doped Si-rich SiCx micro-ring resonator waveguide with a quality factor of 1.7 x 10(4) under an optimized gap spacing of 700 nm away from the bus waveguide, the XAM effect induces a wavelength-converted picosecond all-optical switching between pump and probe signals, which is attributed to a specific free-carrier absorption at probe wavelength caused by the two-photon-absorption induced carriers. The non-degenerate pump-probe analysis also shows a weak Kerr nonlinearity related ultrafast switching response from the changing envelope of the XAM probe pulse at red-shifted wavelength. These observations declare that the nano-scale Si-QDs can provide sufficiently large XAM effect to enable the ultrafast all-optical switching capability for pulsed optical logic applications. To confirm, the Si-QDs doped Si-rich SiCx waveguide modulator-based 1.2 Gb/s all-optical format inversion of a PRZ-OOK data-stream is demonstrated for the first time.

• 出版日期2016-12