Year: 2025
Type: article
Abstract: In recent years, two‐dimensional (2D) niobium oxide dihalides (e.g., NbOI 2 ) have garnered significant research interest in nonlinear photonics due to their prominent second‐order nonlinear optical properties. Integrating these materials with high‐quality‐factor optical microcavities represents a crucial approach for developing high‐performance on‐chip nonlinear optical devices. This work demonstrates NbOI 2 ‐integrated silicon nitride (Si 3 N 4 ) microdisk resonators that achieve second‐harmonic generation under low‐power (sub‐milliwatt) continuous‐wave laser pumping, leveraging the superior second‐order nonlinearity of NbOI 2 and the strong optical field confinement capability of Si 3 N 4 microdisks. The conversion efficiency of the device is calculated to be about 0.024 %/W. The intrinsic lack of inversion symmetry in NbOI 2 crystals avoids the laborious layer‐number‐dependent symmetry screening typically required for other 2D materials, while the developed van der Waals transfer technique provides a universal strategy for integrating niobium oxide dihalides with photonic microcavities. This study not only establishes a material‐photon co‐design strategy for on‐chip nonlinear light sources but also lays a critical foundation for advancing quantum photonic chips and on‐chip metrology systems.
Source: Nanophotonics
Authors: Ning Liu, Qiang Liu, Yutian Lin, Zhihong Zhu, Ken Liu
Institution: National University of Defense Technology
Language: English
Topic: Photonic and Optical Devices
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,995
Funder: Peking University
OpenAlex ID: W4415957523