0000000000192822

AUTHOR

Maria Antonietta Vincenti

showing 4 related works from this author

Z-Scan theory for thin film measurements: Validation of a model beyond the standard approach using ITO and HfO2

2023

The Z-Scan technique is an easy and widespread approach to evaluate the nonlinear optical coefficient of materials. However, the evaluation of the same coefficients for thin films requires complex experimental setups that allow to remove the contributions of the substrate. Here, we propose a simple, yet effective, theoretical approach that allows to include the substrate contribution to the focusing effect when scanning along the propagation axis. The proposed method therefore removes the need of complex experimental setups and paves the way for a simpler retrieval of optical properties of complex nanostructures.

Nonlinear opticsZ-ScanHafniaSettore ING-INF/02 - Campi ElettromagneticiITO
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Tunable Optical Antennas Using Vanadium Dioxide Metal-Insulator Phase Transitions

2019

Here, we investigate the possibility of exploiting the insulator-to-metal transition in vanadium dioxide (VO2) to tune and optically control the resonances of dipole nanoantennas in the visible near-infrared region. We compare the results obtained in the case of antennas completely made by VO2 with those of previous works and highlight the key role of the substrate to perform dynamical tuning. We also present a highly efficient configuration composed of dipole gold antenna loaded with VO2 and give some general guidelines to optimally exploit phase transitions to tune nanodevices.

Phase transitionMaterials scienceBiophysics02 engineering and technologySubstrate (electronics)Nanoantennas Phase-changing materials Plasmonics Vanadium dioxide01 natural sciencesBiochemistrySettore FIS/03 - FISICA DELLA MATERIA010309 opticsVanadium dioxide0103 physical sciencesMetal insulatorPhase-changing materialsPlasmonNanoantennas; Phase-changing materials; Plasmonics; Vanadium dioxidebusiness.industryNanoantennasVanadium dioxideSettore ING-INF/02 - Campi Elettromagnetici021001 nanoscience & nanotechnologyDipoleNanoantennas; Phase-changing materials; Plasmonics; Vanadium dioxide; Biotechnology; Biophysics; BiochemistryOptoelectronicsPlasmonicsCondensed Matter::Strongly Correlated ElectronsAntenna (radio)0210 nano-technologybusinessBiotechnology
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Transient guided-mode resonance metasurfaces with phase-transition materials

2023

We investigate transient, photo-thermally induced metasurface effects in a planar thin-film multilayer based on a phase-transition material. Illumination of a properly designed multilayer with two obliquely incident and phase-coherent pulsed pumps induces a transient and reversible temperature pattern in the phase-transition layer. The deep periodic modulation of the refractive index, caused by the interfering pumps, produces a transient Fano-like spectral feature associated with a guided-mode resonance. A coupled opto-thermal model is employed to analyze the temporal dynamics of the transient metasurface and to evaluate its speed and modulation capabilities. Using near-infrared pump pulses…

guided modemetasurfacephotonicvanadium dioxidetransient gratingSettore ING-INF/02 - Campi Elettromagneticiphase change materialAtomic and Molecular Physics and OpticsOptics Letters
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Reconfigurable nonlinear response of dielectric and semiconductor metasurfaces

2021

Abstract Optically resonant dielectric and semiconductor metasurfaces are an emerging and promising area of nanophotonics and light–matter interaction at the nanoscale. Recently, active tuning of the linear response and nonlinear effects of these components has received an increasing amount of interest. However, so far these research directions have remained separated with only few sporadic works that study their combination beginning to appear in the literature. The evolution of nonlinear metasurfaces based on dielectric and semiconductor materials toward reconfigurable and dynamic components could potentially answer the demand of integrated on-chip components that realize essential functi…

dielectric metasurfaces nanophotonics nonlinear optics second-harmonic generation third-harmonic generationMaterials sciencebusiness.industrydielectric metasurfaces; nanophotonics; nonlinear optics; second-harmonic generation; third-harmonic generationPhysicsQC1-999nonlinear opticsNanophotonicsSecond-harmonic generationNonlinear opticsPhysics::OpticsSettore ING-INF/02 - Campi ElettromagneticiDielectricAtomic and Molecular Physics and OpticsElectronic Optical and Magnetic Materialsthird-harmonic generationNonlinear systemSemiconductorOptoelectronicsnanophotonicsdielectric metasurfacesElectrical and Electronic EngineeringbusinessBiotechnologysecond-harmonic generationNanophotonics
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