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Title: Nonvolatile tuning of Bragg structures using transparent phase-change materials
Bragg gratings offer high-performance filtering and routing of light on-chip through a periodic modulation of a waveguide’s effective refractive index. Here, we model and experimentally demonstrate the use of Sb2Se3, a nonvolatile and transparent phase-change material, to tune the resonance conditions in two devices which leverage periodic Bragg gratings—a stopband filter and Fabry-Perot cavity. Through simulations, we show that similar refractive indices between silicon and amorphous Sb2Se3can be used to induce broadband transparency, while the crystalline state can enhance the index contrast in these Bragg devices. Our experimental results show the promise and limitations of this design approach and highlight specific fabrication challenges which need to be addressed in future implementations.  more » « less
Award ID(s):
2210168 2210169 2003325 2028624
PAR ID:
10541128
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
OPTICA Infobase
Date Published:
Journal Name:
Optical Materials Express
Volume:
13
Issue:
10
ISSN:
2159-3930
Page Range / eLocation ID:
2700
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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