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Title: Thermo-optic VO 2 -based silicon waveguide mid-infrared router with asymmetric activation thresholds and large bi-stability

We report a novel four-port optical router that exploits non-linear properties of vanadium dioxide (VO2) phase-change material to achieve asymmetrical power threshold response with power limiting capability. The scope of this study lies within the concept, modeling, and simulation of the device, with practical considerations in mind for future experimental devices. The waveguide structure, designed to operate at the wavelength of 5.0 µm, is composed of a silicon core with air and silicon dioxide forming the cladding layers. Two ring resonators are employed to couple two straight waveguides, thus four individual ports. One of the ring resonators has a 100-nm-thick VO2layer responsible for non-linear behavior of the device. The router achieves 56.5 and 64.5 dB of power limiting at the forward and reverse operating modes, respectively. Total transmission in the inactivated mode is 75%. Bi-stability and latching behavior are demonstrated and discussed.

 
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Award ID(s):
2149886
PAR ID:
10426325
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Express
Volume:
31
Issue:
14
ISSN:
1094-4087; OPEXFF
Format(s):
Medium: X Size: Article No. 23260
Size(s):
Article No. 23260
Sponsoring Org:
National Science Foundation
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