T. Hutter, S. Mahajan, S. R. Elliott
University of Cambridge, Cambridge, UK
University of Southampton, Southampton, UK
Plasmons, i.e. the collective oscillations of electrons in a metallic nano-structure, lead to strong light scattering, absorption and an enhancement of the local electromagnetic field. In this work, the local electric-field enhancement in a system of dielectric nanoparticles placed very near to a metallic substrate is studied and discussed. Finite-element numerical simulations were used in ...
P. Mikulski, K. Mcilhany, and R. Malek-Madani
United States Naval Academy
Here we present and discuss numerical solutions to the paraxial wave equation using COMSOL (2D, PDE, General Form, time-dependent analysis). Ultimately, the goal is to extend this treatment of free-space beam propagation to the case of propagation through a medium that is non-uniform and subject to non-linear effects where the beam itself is modifying the properties of the medium in which it is ...
D. Grabovi?ki?, J.C. González, P. Benítez, J.C. Miñano
Cedint Universidad Politécnica de Madrid, Madrid, Spain
Negative Refractive Lens (NRL) has shown that an optical system can produce images with details below the classic Abbe diffraction limit. This optical system transmits the electromagnetic fields, emitted by an object plane, towards an image plane producing the same field distribution in both planes. Recently, two devices with positive refraction, the Maxwell Fish Eye lens (MFE) (Leonhardt et al. ...
Determination of the Optical Properties of Individual Gold Nanorods through Numerical Modeling and Experiment
Y. Davletshin, J.C. Kumaradas
Ryerson University, Toronto, ON, Canada
The optical scattering and absorption of gold nanorods (GNRs) depends on its size, shape, and surroundings. This dependence is due to both intrinsic and extrinsic effects. A good understanding of this dependence is needed for applications of GNRs in photo-thermal therapy, optical and opto-acoustic imaging, biosensing, and other photonic areas. Extrinsic effects are caused by the production of ...
I. Ponomarev 1, M. Bayer2, and T. Reinecke1
1Naval Research Laboratory, Washington, DC, USA
2Universität Dortmund, Dortmund, Germany
The influence of disorder on the optical mode spectrum of chains of coupled micron-sized microcavities has been studied both experimentally and theoretically with the help of COMSOL. The disorder is introduced by systematic variation of cavity sizes. The resulting spectra are interpreted in terms of modified dispersion for propagation along the chains accompanied by the appearance of localized ...
A. Alabastri, R. Krahne, A. Giugni, G. Das, R. P. Zaccaria, M. Zanella, I. Franchini, and E. di Fabrizio
Italian Institute of Technology (IIT)
We studied the optical phonon excitations (LO) of ordered arrays of dot/ rod core-shell CdSe/ CdS nanorods by Raman spectroscopy. Upon deposition on planar substrates the nanorods formed super-lattice structures via side-by side assembly into tracks over some microns of length. COMSOL Multiphysics software has been used to calculate the magnitude of the electric field generated by the ...
S. Ni, C. Yang Koh, S. Kooi, and E. Thomas
Institute for Soldier Nanotechnologies
Dept. of Materials Science and Eng.
Recently, the concepts of fractal geometry have been introduced into electromagnetic and plasmonic metamaterials. With their self-similarity, structures based on fractal geometry should exhibit multi-band character with high Q factors due to the scaling law. However, there exist few studies of phononic metamaterials having fractal geometry. COMSOL is used to investigate vector elastic and ...
X. Ni, A. Kildishev, E. Narimanov, and L. Prokopeva
Purdue University, West Lafayette, IN, USA
Russian Academy of Sciences, Novosibirsk, Russia
We model an ideal optical black hole device in COMSOL Multiphysics as an electromagnetic scattering problem. The device is illuminated with a Gaussian beam which is focused at a fixed position in horizontal direction (x0) and different positions in vertical direction (y0). The device is modeled as a cylindrical system with a gradient-index shell and absorbing core. Using the classical paraxial ...
J. J. Mahakud, D. Sengupta
Institute of Technical Education & Research, Siksha 'O' Anusandhan University, Bhubaneswar, Odisha, India
Solar energy is the cleanest form of renewable energy. The most popular form of utilization of solar energy is through the use of photovoltaic cells. Currently the efficiency of available solar cells lies below 20%. To increase the efficiency, multi-junction can be used in solar cells. While developing such devices we need platform to study various characteristics and parameters to optimize ...
Implementation of an 2D electro-thermal model for power semiconductor devices simulation: application on gallium nitride
Benbakhti, B., Rousseau, M., De Jeager, J.C.
Generally, the power dissipation in a semiconductor device generates self-heating effect. This effect is very significant in power applications using Gallium Nitride. Taking into account heating effects enables us to understand physical phenomena observed in experiments like the low saturation velocity. In this paper, numerical simulations were carried out to study the influence of thermal ...