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Abstract 2D metal carbides and nitrides (MXene) are promising material platforms for on‐chip neural networks owing to their nonlinear saturable absorption effect. The localized surface plasmon resonances in metallic MXene nanoflakes may play an important role in enhancing the electromagnetic absorption; however, their contribution is not determined due to the lack of a precise understanding of its localized surface plasmon behavior. Here, a saturable absorber made of MXene thin film and a silicon waveguide with MXene flakes overlayer are developed to perform neuromorphic tasks. The proposed configurations are reconfigurable and can therefore be adjusted for various applications without the need to modify the physical structure of the proposed MXene‐based activator configurations via tuning the wavelength of operation. The capability and feasibility of the obtained results of machine‐learning applications are confirmed via handwritten digit classification task, with near 99% accuracy. These findings can guide the design of advanced ultrathin saturable absorption materials on a chip for a broad range of applications.
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Nonlinear absorption in phthalocyanine thin films and solutions using a continuous wave laser
The nonlinear absorption of nanoscale thin films of iron phthalocyanine, zinc phthalocyanine, and metal-free phthalocyanine fabricated via thermal evaporation at various deposition temperatures was studied using the open-aperture z-scan method with a continuous wave laser. A solution of tetra-tert-butyl-phthalocyanine in chloroform was also studied via z-scan. The thin films exhibit pronounced saturable absorption, with the degree of nonlinearity highly dependent on the type of metal complex. No significant correlation was found between deposition temperature and nonlinear absorption. The liquid sample exhibits a transition from saturable absorption to reverse saturable absorption at high irradiance.
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- Award ID(s):
- 2018653
- PAR ID:
- 10386661
- Date Published:
- Journal Name:
- Journal of Nonlinear Optical Physics & Materials
- Volume:
- 31
- Issue:
- 04
- ISSN:
- 0218-8635
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1142/S0218863522500187
