Details

Autor(en) / Beteiligte

• Oser, Dorian
• Pérez-Galacho, Diego
• Alonso-Ramos, Carlos
• Le Roux, Xavier
• Tanzilli, Sébastien
• Vivien, Laurent
• Labonté, Laurent
• Cassan, Éric

Titel

Subwavelength engineering and asymmetry: two efficient tools for sub-nanometer-bandwidth silicon Bragg filters

Ist Teil von

• Optics letters, 2018-07, Vol.43 (14), p.3208-3211

Ort / Verlag

United States: Optical Society of America

Erscheinungsjahr

2018

Link zum Volltext

Quelle

Optica Publishing Group Journals

Beschreibungen/Notizen

• Bragg filters stand as key building blocks of the silicon-on-insulator (SOI) photonics platform, allowing the implementation of advanced on-chip signal manipulation. However, achieving narrowband Bragg filters with large rejection levels is often hindered by fabrication constraints and imperfections. Here, we show that the combination of single-side corrugation asymmetry and subwavelength engineering provides a narrowband response with large corrugations, overcoming minimum feature size constraints of conventional Si Bragg filters. We comprehensively study the impact of the corrugation asymmetry in conventional and subwavelength single-etched SOI Bragg filters, showing their potential for bandwidth reduction. Finally, we experimentally demonstrate novel subwavelength geometry based on shifted corrugation teeth, achieving null-to-null bandwidths and rejections of 0.8 nm and 40 dB for the symmetric configuration and 0.6 nm and 15 dB for the asymmetric case.