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2023-05-12
Saldutti, Marco, Yu, Yi, Kristensen, Philip Trøst, Kountouris, George, Mørk, Jesper.  2022.  Carrier dynamics in nonlinear photonic nanocavities with extreme dielectric confinement. 2022 IEEE Photonics Conference (IPC). :1–2.
We show that a new type of dielectric cavity featuring deep sub-wavelength light confinement allows a significant speedup of all-optical signal processing functionalities, without compromising the energy efficiency. The effect is due to enhanced diffusion dynamics in an unconventional geometry.
ISSN: 2575-274X
2017-03-08
Torabi, A., Shishegar, A. A..  2015.  Combination of characteristic Green's function technique and rational function fitting method for computation of modal reflectivity at the optical waveguide end-facet. 2015 International Conference on Photonics, Optics and Laser Technology (PHOTOPTICS). 2:14–21.

A novel method for computation of modal reflectivity at optical waveguide end-facet is presented. The method is based on the characteristic Green's function (CGF) technique. Using separability assumption of the structure and rational function fitting method (RFFM), a closed-form field expression is derived for optical planar waveguide. The uniform derived expression consists of discrete and continuous spectrum contributions which denotes guided and radiation modes effects respectively. An optimization problem is then defined to calculate the exact reflection coefficients at the end-facet for all extracted poles obtained from rational function fitting step. The proposed CGF-RFFM-optimization offers superior exactness in comparison with the previous reported CGF-complex images (CI) technique due to contribution of all components of field in the optimization problem. The main advantage of the proposed method lies in its simple implementation as well as precision for any refractive index contrast. Excellent numerical agreements with rigorous methods are shown in several examples.

2015-05-05
Ponti, C., Pajewski, L., Schettini, G..  2014.  Simulation of scattering by cylindrical targets hidden behind a layer. Ground Penetrating Radar (GPR), 2014 15th International Conference on. :560-564.

Through-wall sensing of hidden objects is a topic that is receiving a wide interest in several application contexts, especially in the field of security. The success of the object retrieval relies on accurate scattering models as well as on reliable inversion algorithms. In this paper, a contribution to the modeling of direct scattering for Through-Wall Imaging applications is given. The approach deals with hidden scatterers that are circular cross-section metallic cylinders placed below a dielectric layer, and it is based on an analytical-numerical technique implementing Cylindrical Wave Approach. As the burial medium of the scatterers may be a dielectric of arbitrary permittivity, general problems of scattering by hidden objects may be considered.When the burial medium is filled with air, the technique can simulate objects concealed in a building interior. Otherwise, simulation of geophysical problems of targets buried in a layered soil can be performed. Numerical results of practical cases are reported in the paper, showing the potentialities of the technique for its use in inversion algorithms.