[TuA1] 2D Materials: Emergent Device Applications

9:00 AM - 9:30 AM JST(12:00 AM - 12:30 AM UTC)

[TuA1-02 Invited] Electrically Tunable Nonlinear Optic Response in Ferroelectric NbOBr₂ Integrated Photonics

〇Sanghoon Chae¹ (1. Nanyang Technological University (Singapore))

Niobium oxide dihalides exhibit vanishing interlayer electronic coupling and strong, thickness-dependent second-harmonic generation (SHG), making them promising for free-space nonlinear optics (NLO). However, practical on-chip integration demands not only high NLO efficiency but also robust electrical tunability, a critical feature yet to be achieved. Here, we demonstrate the first in-situ electrically tunable NLO response in a photonic integrated circuit (PIC) using NbOBr₂, a material that combines strong intrinsic second-order susceptibility with exceptional tunability from in-plane ferroelectricity. In the PIC platform, NbOBr₂ achieves enhanced SHG efficiency due to reduced index contrast and superior modulation capability enabled by its strong ferroelectric polarization. We realize dynamic and non-volatile SHG modulation exceeding 53%, with the polarization state retained after electric field removal. This work establishes 2D ferroelectric NbOBr₂ as a versatile platform for scalable, reconfigurable, and ultracompact NLO devices, opening new avenues for tunable light sources, optical computing, and quantum photonics.