[TuP3D] D. Photonic devices and related technologies

[TuP3D-10] Side-modes Reduction in CirD Lasers Using AlGaAs Funnel Structures

〇Haruya Kume¹, Masahiko Kondow¹, Rubing Zuo¹, Masato Morifuji¹, Hirotake Kajii¹, Akihiro Maruta¹, Tetsuya Yagi¹, Nobuhiko Kikuchi¹ (1. The Univ. of Osaka (Japan))

This study demonstrates that AlGaAs funnel structures are essential for enabling accurate top-view optical measurements of CirD lasers. Although top-view measurement offers a simpler, non-destructive alternative to conventional cross-sectional methods, previous assessments were hindered by broad side-modes that interfered with the evaluation of the primary Whispering Gallery Mode (WGM). This research show that integrating an AlGaAs funnel effectively suppresses these disruptive side-modes, thereby clarifying the WGM signal. This suppression occurs because the funnel structure overlaps with the side-modes' magnetic field distributions, significantly reducing their Q-factors. By ensuring that side-modes do not interfere with the main signal, the funnel structure successfully validates the use of top-view measurements as a reliable method for evaluating cavity emissions.