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Abstract The characteristic metal–insulator phase transition (MIT) in vanadium dioxide results in nonlinear electrical transport behavior, allowing VO2devices to imitate the complex functions of neurological behavior. Chemical doping is an established method for varying the properties of the MIT, and interstitial dopant boron has been shown to generate a unique dynamic relaxation effect in individual B‐VO2particles. This paper describes the first demonstration of an electrically stimulated B‐VO2proto‐device which manifests a time‐dependent critical transformation temperature and switching voltage derived from the coupling of dopant diffusion dynamics and the metal–insulator transition of VO2. During quasi‐steady current‐driven transitions, the electrical responses of B‐VO2proto‐devices show a step‐by‐step progression through the phase transformation, evidencing domain transformations within individual particles. The dynamic relaxation effect is shown to increase the critical switching voltage by up to 41% (ΔVcrit =0.13 V) and also to increase the resistivity of the M1 phase of B‐VO2by 14%, imbuing a memristive response derived from intrinsic material properties. These observations demonstrate the dynamic relaxation effect in B‐VO2proto‐devices whose electrical transport responses can be adjusted by electronic phase transitions triggered by temperature but also by time as a result of intrinsic dynamics of interstitial dopants.
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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
- 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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