Enhanced Transition-Temperature Reduction in a Half-Sphere 
<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:mi>Au</mml:mi><mml:mo>/</mml:mo><mml:msub><mml:mi>VO</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>
 Core-Shell Structure: Local Plasmonics versus Induced Stress and Percolation Effects

Balin, Igal; Wang, Shancheng; Wang, Peikui; Long, Yi; Abdulhalim, Ibrahim

doi:10.1103/physrevapplied.11.034064

Cited by 15 publications

(5 citation statements)

References 68 publications

(73 reference statements)

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“…This structure can be experimentally synthesized due to the transfer of electrons from gold to VO 2 . The work function of gold (4.8 eV) is smaller than that of VO 2 (5.4 eV) and also the gold Fermi level is close to the conduction band of VO 2 in the phase semiconductor (Figure ). Also, the absorption peak wavelengths are in the near-infrared (NIR) range because of which at this wavelength there is a balance between light scattering and absorption for deep-tissue imaging .…”

Section: Resultsmentioning

confidence: 99%

Photothermal and Photoacoustic Response of a VO₂@Au Nanoshell Irradiated by a Nanosecond Laser Pulse

2022

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Plasmonic nanoparticles (PNPs) are considered as a proper mediator in photothermal therapy due to their capability to efficiently convert the absorbed light energy into localized heat. As the localized heat diffuses during therapy processes, it is crucial to control and detect the temperature in a non-invasive way. Synthesizing a new generation of PNPs that utilize optical phasechange materials leads to a tunable photothermal response without geometrical variation. This tunability originates from the prompt variation of optical and thermal properties during the phase-change transition. In this paper, we numerically study the photothermal response of a VO 2 @Au nanoshell in an aqueous medium when irradiated by a nanosecond pulsed laser (5 ns). For the temperature profiles, we simultaneously solve a self-consistent multiphysics problem consisting of electromagnetism and thermodynamics. We do our calculations for two wavelengths of 658 and 737 nm where the absorption spectrum of the nanoshell has two extrema during the VO 2 core's phase-change transition. Finally, for the two selected wavelengths, by coupling the structural dynamic physics to the problem, we calculate the acoustic pressure signals generated by the photothermal expansion of both the nanoshell and its surrounding medium. This photoacoustic signal could be considered as a non-invasive method to measure the local temperature in deep tissues accurately.

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Section: Resultsmentioning

confidence: 99%

Photothermal and Photoacoustic Response of a VO₂@Au Nanoshell Irradiated by a Nanosecond Laser Pulse

2022

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“…[50] In this work, the effect of Au nanoislands on the crystal structure of VO 2 can be ruled out, which is formed after the VO 2 crystallization, but rather provides n-type carriers during the heating process due to electron injection (see Figure S4, Supporting Information). [51][52][53] Under dark state, the electrons in Au are transferred to the VO 2 film due to metalsemiconductor contact, leading to a lower phase transition temperature and higher initial current.…”

Section: Resultsmentioning

confidence: 99%

Phase‐Transition‐Induced VO₂ Thin Film IR Photodetector and Threshold Switching Selector for Optical Neural Network Applications

Zhou

Liang

Zhen

et al. 2021

Adv Elect Materials

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As the architecture of choice for future artificial-intelligent systems, the ideas of in-memory-and in-sensor-computing paradigms based on nonvon-Neumann architecture possess broad application prospects such as neuromorphic and sensor-memory-processor fusion systems. At the same time, these promising applications put diversified and strict requirements on the device performances, such as fast response to external signals, robust data security, and 3D integration potential. In this work, Au@VO 2 IR photodetectors and Ti/Au/VO 2 /Ti/Au threshold switching selectors are constructed, where the VO 2 thin films are realized by magnetron sputtering and water-vapor assisted post-annealing. Fast IR response is achieved in Au@ VO 2 photodetectors through a surface plasmon resonance-assisted metalinsulator transition. Furthermore, electroforming-free, tunable threshold voltage, steep switching slope, and selectivity of more than two orders of magnitude are observed in Ti/Au/VO 2 /Ti/Au threshold switching selector. Combining the functionalities of photodetection and selector, a VO 2 -based optical convolution engine demonstrates accurate and secure image-processing capability. These VO 2 -based devices are demonstrated as promising candidates for novel non-volatile memory, neuromorphic computing and sensor-memory-processor fusion applications.

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“…Combining the results of the above transmittance thermal hysteresis loop, we can conclude that the overlayer has not induced weakening of the phase transition performance. Based on the transmittance spectra, solar energy modulation ability of the samples was calculated according to the formula below [29]:…”

Section: Resultsmentioning

confidence: 99%

A Novel Method for Notable Reducing Phase Transition Temperature of VO2 Films for Smart Energy Efficient Windows

et al. 2019

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Although Vanadium dioxide (VO2) has a potential application value for smart energy efficient windows because of its unique phase transition characteristic, there are still many obstacles that need to be overcome. One challenge is to reduce its high transition temperature (ζc = 68 °C) to near room temperature without causing its phase transition performance degradation. In this paper, a novel method was employed that covered a 3 nm ultra-thin heavy Cr-doped VO2 layer on the pure VO2 films. Compared with the as-grown pure VO2, obviously, phase transition temperature decreasing from 59.5 °C to 48.0 °C was observed. Different from previous doping techniques, almost no phase transition performance weakening occurred. Based on the microstructure and electrical parameters measurement results, the mechanism of ζc reducing was discussed. The upper ultra-thin heavy Cr-doped layer may act as the induced role of phase transition. With temperature increasing, carrier concentration increased from the upper heavy Cr-doped layer to the bottom pure VO2 layer by diffusion, and induced the carrier concentration reach to phase transition critical value from top to bottom gradually. The present method is not only a simpler technique, but also avoids expensive alloy targets.

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Enhanced Transition-Temperature Reduction in a Half-Sphere Au/VO2 Core-Shell Structure: Local Plasmonics versus Induced Stress and Percolation Effects

Abstract: Enhanced transition-temperature reduction in a half-sphere Au/VO2 core-shell structure : local plasmonics versus induced stress and percolation effects. Physical Review Applied, 11(3), 034064-.

Cited by 15 publications

References 68 publications

Photothermal and Photoacoustic Response of a VO₂@Au Nanoshell Irradiated by a Nanosecond Laser Pulse

Photothermal and Photoacoustic Response of a VO₂@Au Nanoshell Irradiated by a Nanosecond Laser Pulse

Phase‐Transition‐Induced VO₂ Thin Film IR Photodetector and Threshold Switching Selector for Optical Neural Network Applications

A Novel Method for Notable Reducing Phase Transition Temperature of VO2 Films for Smart Energy Efficient Windows

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Enhanced Transition-Temperature Reduction in a Half-Sphere Au/VO2 Core-Shell Structure: Local Plasmonics versus Induced Stress and Percolation Effects

Abstract: Enhanced transition-temperature reduction in a half-sphere Au/VO2 core-shell structure : local plasmonics versus induced stress and percolation effects. Physical Review Applied, 11(3), 034064-.

Cited by 15 publications

References 68 publications

Photothermal and Photoacoustic Response of a VO2@Au Nanoshell Irradiated by a Nanosecond Laser Pulse

Photothermal and Photoacoustic Response of a VO2@Au Nanoshell Irradiated by a Nanosecond Laser Pulse

Phase‐Transition‐Induced VO2 Thin Film IR Photodetector and Threshold Switching Selector for Optical Neural Network Applications

A Novel Method for Notable Reducing Phase Transition Temperature of VO2 Films for Smart Energy Efficient Windows

Contact Info

Product

Resources

About

Photothermal and Photoacoustic Response of a VO₂@Au Nanoshell Irradiated by a Nanosecond Laser Pulse

Photothermal and Photoacoustic Response of a VO₂@Au Nanoshell Irradiated by a Nanosecond Laser Pulse

Phase‐Transition‐Induced VO₂ Thin Film IR Photodetector and Threshold Switching Selector for Optical Neural Network Applications