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

• DOI: 10.1007/s12200-025-00147-5
• Publication Date: 2025-03-14T02:23:31Z
• Authors: Ran Hao; Bilin Ye; Jinhong Xu; Yonggang Zou
• Keywords: Crystal (programming language); Q factor

Abstract Bound states in the continuum (BICs) offer a promising solution to achieving high-quality factor ( Q factor) cavities. However, finite-size effects severely deteriorate BIC mode practical applications. This paper reports experimental demonstration of an electrically pumped 940 nm laser based on optimized cavity, high up $$1.18 \times 10^4$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mn>1.18</mml:mn> <mml:mo>×</mml:mo> <mml:msup> <mml:mn>10</mml:mn> <mml:mn>4</mml:mn> </mml:msup> </mml:mrow> </mml:math> even with finite photonic crystal footprint, which is two orders magnitude larger than un-optimized design. Two strategies have been systematically investigated mitigate effects: reflective cavity design and graded Both methods significantly improve factor, demonstrating effectiveness preserving characteristics finite-sized In addition, boundary fabricated experimentally characterized demonstrate its lasing characteristics. The exhibits single-mode operation signal-to-noise ratio 38.6 dB. These results pave way for future designs BICs size real applications, promoting performance BIC-based integrated lasers. Graphical