Drift-Diffusion and Ballistic Transport Modeling in III-Nitride Multiple-QW Light Emitting Structures
M.V. Kisin, and H.S. El-Ghoroury
Ostendo Technologies Inc., Carlsbad, CA, USA
COMSOL-based modeling software developed at Ostendo Technologies allows detailed simulation of semiconductor lasers and light-emitting diodes. In this work, we study the inhomogeneity of the carrier injection into optically active quantum wells of polar and nonpolar III-nitride light emitters. Despite the absence of polarization-induced potential barriers, the nonpolar multiple-quantum well ...
S. Tuccio , A. Alabastri, L. Razzari, A. Toma, C. Liberale, R. Proietti Zaccaria, F. De Angelis, G. Das, E. di Fabrizio
Istituto Italiano di Tecnologia, Genova, Italy
Nanoantennas have been successfully employed in a wide set of applications. We show the possibility to expand usual nanoantenna functionalities in the THz domain with a gold dipole nanoantenna. We considered an array of aligned planar gold nanoantennas over a silicon substrate. The high near field enhancement, localized at the device ends, indicates potential uses for THz spectroscopy and ...
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. ...
Complex K-Bands Calculation for Plasmonic Crystal Slabs by Means of Weak Formulation of Helmholtz's Eigenvalue Equation
G. Parisi, P. Zilio, F. Romanato
University of Padova, Padova, Italy
We present a Finite Element Method (FEM) to calculate the complex valued k(?) dispersion curves of a photonic crystal slab in presence of both dispersive and lossy materials. In particular the method can be exploited to study plasmonic crystal slabs. We adopt Perfectly Matched Layers (PMLs) in order to truncate the open boundaries of the model, including their related anisotropic permittivity and ...
Modelling Ultra-short Pulse Laser Ablation of Dielectric Materials Using multiple Rate Equations - new
P. Boerner, K. Wegener
Institute of Machine Tools and Manufacturing, ETH Zurich, Zurich, Switzerland
Ultrafast lasers are widely applied in micromachining, material science and physics. In industry, picosecond lasers are becoming more and more established. For pulse lengths shorter than the electron-phonon coupling time, heat affected zones are negligible. Thermally sensitive materials can be processed using ultrashort pulse laser radiation. Multi-component materials and poorly absorbing ...
H. Karakuzu, M. Dubov, S. Boscolo
 Aston University, Birmingham, UK
We present an optimization procedure to improve the propagation properties of the depressed-cladding, buried micro-structured waveguides formed in a z-cut lithium niobate (LN) crystal by high repetition rate femtosecond (fs) laser writing. It is shown that the propagation wavelength for which the confinement losses of ordinary (O) and extraordinary ordinary (E) polarizations are below 1 dB/cm ...
G. Latha, P. Nair
SSN College of Engineering, Chennai, Tamil Nadu, India
In a solid core PCF, structural parameters and the number of rings in the cladding region decide confinement losses, dispersion coefficients as well as bending losses. This paper evaluates some of commercially available solid core photonic crystal fibers. The dispersion coefficients and sensitivity of these fibers are estimated using COMSOL Multiphysics®, and compared with the theoretical values ...
H.-H. Yeh, Y.-F. Chau
Department of Electronic Engineering, Ching Yun University, Taiwan
High birefringence induced by complex unit cells of elliptical air holes in photonic crystal fibers (PCFs) is analyzed numerically using COMSOL Multiphysics. Two types of our proposed PCFs and a previous structure are investigated. The statistical correlations between the birefringence and the various parameters are obtained. The birefringence is found to be largely dependent on the variation of ...
M. Goncalves, T. Makaryan, G. Papageorgiou, U. Herr, and O. Marti
Ulm University - Inst. of Experimental Physics, Ulm, Germany
Yerevan State University, Yerevan, Armenia
Ulm University - Institute of Micro and Nanomaterials, Ulm, Germany
Surface enhanced Raman scattering (SERS) investigations of silver and gold triangular nanoparticles reveal strong field enhancements at the corners of the particles. Though the measurements were done at wavelengths far from the surface-plasmon resonance of the particles, large field enhancements can be generated by near-field coupling between the triangular particles and smaller metal ...