Performance optimization of planar photonic crystal bound states in the continuum cavities: mitigating finite-size effects  

作　　者：Ran Hao Bilin Ye Jinhong Xu Yonggang Zou 

机构地区：[1]State Key Laboratory on High Power Semiconductor Lasers,Changchun University of Science and Technology,Changchun 130022,China [2]College of Optical and Electronic Technology,China Jiliang University,Hangzhou 310018,China

出　　处：《Frontiers of Optoelectronics》2025年第1期53-62,共10页光电子前沿(英文版)

摘　　要：Bound states in the continuum (BICs) offer a promising solution to achieving high-quality factor (Q factor) cavities. However, finite-size effects severely deteriorate the BIC mode in practical applications. This paper reports the experimental demonstration of an electrically pumped 940 nm laser based on optimized BIC cavity, achieving a high Q factor of up to 1.18 × 104 even with finite photonic crystal footprint, which is two orders of magnitude larger than un-optimized BIC design. Two strategies have been systematically investigated to mitigate finite-size effects: reflective photonic crystal cavity design and graded photonic crystal cavity design. Both methods significantly improve the Q factor, demonstrating the effectiveness of preserving BIC characteristics in finite-sized photonic crystal cavities. In addition, the reflective boundary photonic crystal design is fabricated and experimentally characterized to demonstrate its lasing characteristics. The fabricated laser exhibits single-mode operation with a signal-to-noise ratio of 38.6 dB. These results pave the way for future designs of BICs with finite size in real applications, promoting the performance of BIC-based integrated lasers.

关 键 词：Bound states in the continuum High-quality factor Graded photonic crystals Electrical pumped laser 

分 类 号：O734[理学—晶体学]