表題番号：2025C-533 日付：2026/02/28
研究課題Design of a Surface-Illuminated Ultrathin Silicon Photodetector based on Guided Mode Resonance
研究者所属（当時） 資格 氏名
（代表者） 理工学術院 情報生産システム研究センター 助教 馮　偉男
研究成果概要
During this academic year, my research activities primarily focused on the following two directions:

1. Design of Near-Infrared Photodetectors and Surface-Emitting Lasers Based on Guided Mode Resonance

Building on last year’s results, we demonstrated that guided mode resonance (GMR) can effectively concentrate optical energy within the absorption layer of silicon-based near-infrared devices, thereby enhancing the absorption efficiency. This year, we extended our investigation to the design of surface-emitting lasers. While vertical-cavity surface-emitting lasers (VCSELs) dominate the current market, their output power remains limited. To address this issue, we proposed a hybrid structure that combines guided mode resonance with ring resonance. This configuration significantly increases the Q-factor of the active layer, leading to improved surface-emission power. The project is still ongoing, and the interim results have been incorporated into a master’s thesis within our research group.

2. Nanoscale Optical Field Concentration Using an All-Dielectric Conical Tip

Achieving nanoscale optical field concentration using non-metallic probes has long been considered challenging. In this work, we employed high-refractive-index materials (such as Si and Ge) to construct dielectric conical tips that support strong Mie resonances. When illuminated with radially polarized light, the transverse electric field components are efficiently converted into longitudinal components and concentrated at the tip apex. Owing to the large refractive index contrast at the material interface, a pronounced electric-field enhancement is achieved at the apex. This design demonstrates that all-dielectric probes can achieve superfocusing performance comparable to metallic SPP-based structures. The results have been published in Optics Express.