We designed and demonstrated experimentally a silicon photonics integrated dynamic polarization controller. The overall size of the dynamic polarization controller on chip is 2.830mm×0.210mm×1mm. The modulation bandwidth is 30 kHz. By using a variable step simulated annealing approach, we achieve a dynamic polarization extinction ratio greater than 25 dB. A numerical simulation method was used to optimize the relevant parameters of the dynamic polarization controller. It is expected that the dynamic polarization controller can be utilized in fiber communication systems or silicon photonics integrated quantum communication systems to minimize the size and decrease the cost further.

We demonstrate a novel type of miniature spectrometer based on a Fourier transform spectrometer (FTS) chip with a dense output array and a commercial photodetector (PD) array. The FTS chip has an output array cycle of 20 μm and consists of 51 Mach–Zehnder interferometers (MZIs), and the PD array is a commercial linear charged coupled device (CCD). An achromatic triplet lens is used to image the MZI output interferogram onto the CCD with a small aberration. Our experiment result shows that a free spectral range (FSR) from 489 nm to 584 nm and a retrieved spectral resolution of 3.5 nm at 532 nm are obtained. The achieved properties show that our spectrometer has the potential to outperform the best commercial compact one in terms of most performance indices.

We present compact silicon-arrayed waveguide grating routers (AWGRs) with three different channel spacings of 20, 6.4, and 3.2 nm for optical interconnect systems. The AWGR with the 20 nm channel spacing shows a low loss of 2.5 dB and a low crosstalk of 20 dB and has a footprint of only 0.27 mm×0.19 mm. The AWGR with the channel spacing of 6.4 nm has loss ranging from 3 to 8 dB, and the crosstalk is 18 dB. As for the 3.2 nm channel spacing, the loss is about 4 dB, and the crosstalk is 12 dB.

An optical sensor is designed to support the Fano effect based on a compound resonant waveguide grating (CRWG). The transmission spectra of the CRWG are investigated by utilizing a theoretical method that combines the temporal coupled mode theory with the eigenmode information of the grating structure. The theoretical results, which are observed to agree closely with those acquired by rigorous coupled-wave analysis, show that the linewidth of the transmission spectrum decreases upon increasing the distance between the grating strips, and the central resonance frequency decreases as the refractive index of the analyte increases. Here, the proposed CRWG structures will find potential uses in optical sensing.