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Title: Integrated polarization-free Bragg filters with subwavelength gratings for photonic sensing
We present polarization-free Bragg filters having subwavelength gratings (SWGs) in the lateral cladding region. This Bragg design expands modal fields toward upper cladding, resulting in enhanced light interaction with sensing analytes. Two device configurations are proposed and examined, one with index-matched coupling between transverse electric (TE) and transverse magnetic (TM) modes and the other one with hybrid-mode (HM) coupling. Both configurations introduce a strong coupling between two orthogonal modes (either TE-TM or HM1-HM2) and rotate the polarization of the input wave through Bragg reflection. The arrangements of SWGs help to achieve two configurations with different orthogonal modes, while expanding modal profiles toward the upper cladding region. Our proposed SWG-assisted Bragg gratings with polarization independency eliminate the need for a polarization controller and effectively tailor the modal properties, enhancing the potential of integrated photonic sensing applications.  more » « less
Award ID(s):
2144568
PAR ID:
10484910
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Express
Volume:
32
Issue:
2
ISSN:
1094-4087; OPEXFF
Format(s):
Medium: X Size: Article No. 2147
Size(s):
Article No. 2147
Sponsoring Org:
National Science Foundation
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