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Title: Determination of the nonlinear thermo-optic coefficient of silicon nitride and oxide using an effective index method
There is little literature characterizing the temperature-dependent thermo-optic coefficient (TOC) for low pressure chemical vapor deposition (LPCVD) silicon nitride or plasma enhanced chemical vapor deposition (PECVD) silicon dioxide at temperatures above 300 K. In this study, we characterize these material TOC’s from approximately 300-460 K, yielding values of (2.51 ± 0.08) · 10−5K−1for silicon nitride and (5.67 ± 0.53) · 10−6K−1for silicon oxide at room temperature (300 K). We use a simplified experimental setup and apply an analytical technique to account for thermal expansion during the extraction process. We also show that the waveguide geometry and method used to determine the resonant wavelength have a substantial impact on the precision of our results, a fact which can be used to improve the precision of numerous ring resonator index sensing experiments.  more » « less
Award ID(s):
2023730
PAR ID:
10385367
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Express
Volume:
30
Issue:
26
ISSN:
1094-4087; OPEXFF
Format(s):
Medium: X Size: Article No. 46134
Size(s):
Article No. 46134
Sponsoring Org:
National Science Foundation
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