[10a-E101-1~11] 15.4 III-V-group nitride crystals

10:00 AM - 10:15 AM JST(1:00 AM - 1:15 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation Award

[10a-E101-5] Fabrication and Characterization of a Visible-Light GaN Modulator for Photonic Integration

〇Takumi Ito¹, Toshihiko Kishino¹, Hironobu Nakazawa¹, Takahiro Serikawa¹, Hisashi Ogawa¹ (1.Nichia Corporation)

Keywords:

Phase Modulator,Photonic Integrated Circuit,Gallium Nitride

Toward monolithic integration with GaN laser diodes, GaN-based optical modulators should be fabricated on a GaN substrate platform compatible with GaN-LDs. In this work, we fabricated a ridge-type phase modulator with a p-i-n layer structure on a GaN substrate and evaluated its optical modulation characteristics at a wavelength of 460 nm. The measured voltage dependence of the optical signal yielded a VπL product of 1.28 V·cm. The modulation bandwidth was approximately 20 MHz and was in good agreement with the calculated RC cutoff frequency. This agreement suggests that the present bandwidth is mainly limited by the device and electrode structures. These results demonstrate the feasibility of a GaN-substrate-based visible-light modulator and provide a guideline for improving the device and electrode designs for GaN light-source integration.