Realization of advanced passive silicon photonic devices with subwavelength grating structures developed by efficient inverse design

Abstract

Compact passive silicon photonic devices with high performance are always desired for future largescale photonic integration. Inverse design provides a promising approach to realize new-generation photonic devices, while it is still very challenging to realize complex photonic devices for most inverse designs reported previously due to the limits of computational resources. Here, we present the realization of several representative advanced passive silicon photonic devices with complex optimization, including a sixchannel mode (de)multiplexer, a broadband 90 deg hybrid, and a flat-top wavelength demultiplexer. These devices are designed inversely by optimizing a subwavelength grating (SWG) region and the multimode excitation and the multimode interference are manipulated. Particularly, such SWG structures are more fabrication-friendly than those random nanostructures introduced in previous inverse designs. The realized photonic devices have decent performances in a broad bandwidth with a low excess loss of <1 dB, which is much lower than that of previous inverse-designed devices. The present inverse design strategy shows great effectiveness for designing advanced photonic devices with complex requirements (which is beyond the capability of previous inverse designs) by using affordable computational resources.

Silicon–Organic Hybrid Electro-Optic Modulator and Microwave Photonics Signal Processing Applications

“…Integration is an inevitable trend in future photonics technology development, which can greatly reduce the size, weight, and power consumption (SWaP) of the system. As a key component in highly integrated optoelectronic systems, electro-optic modulators (EOMs) have great potential for applications in fields such as optical communications [1,2] and microwave photonics [3][4][5][6][7][8][9]. The high-performance EOMs should simultaneously have large electro-optic (EO) response bandwidth, small half-wave voltage V π , and short device length L. The common EOMs can be divided into three categories according to the materials: LiNbO 3 (LN), Si, and EO polymer.…”