Technical Papers and Presentations

Here you will find presentations given at COMSOL Conferences around the globe. The presentations explore the innovative research and products designed by your peers using COMSOL Multiphysics. Research topics span a wide array of industries and application areas, including the electrical, mechanical, fluid, and chemical disciplines. Use the Quick Search to find presentations pertaining to your application area.

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 ...

Non-Equilibrium Quantum Well Populations and Optical Characteristics of III-Nitride Lasers and Light-Emitting Diodes

M. Kisin, and H. El-Ghoroury
Ostendo Technologies, Inc.
Carlsbad, CA

COMSOL-based Ostendo’s Optoelectronic Device Modeling Software (ODMS) has been updated to include effects of non-equilibrium QW populations in semiconductor light-emitting and laser diodes. III-nitride light emitters with different levels of polarity have been compared as an illustrative example of ODMS performance. Modeling proved that high intra-QW recombination rates in III-nitride light ...

Solving the Paraxial Wave Equation using COMSOL

P. Mikulski, K. Mcilhany, and R. Malek-Madani
United States Naval Academy
Annapolis, MD

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 ...

Analysis of Super Imaging Properties of Spherical Geodesic Waveguide Using COMSOL Multiphysics

D. Grabovi?ki?[1], J.C. González[1], P. Benítez[1], J.C. Miñano[1]
[1]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[1], P. Zilio[1], F. Romanato[1]
[1]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 ...

Optimization of Micro-Structured Waveguides in Lithium Niobate (Z-Cut) - new

H. Karakuzu[1], M. Dubov[1], S. Boscolo[1]
[1] 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 ...

Vertically Emitting Microdisk Lasers

L. Mahler, A. Tredicucci, and F. Beltram
NEST-INFM and Scuola Normale Superiore, Pisa, Italy

We describe the modeling of microdisk lasers displaying vertical emission. The devices are THz quantum cascade lasers with metallic gratings fabricated along the circumference.  The emission properties of the fabricated devices are well explained by the model, good mode control is obtained, and the collected power from a patterned device is increased 50 times with respect to unpatterned ...

Near-fields in Arrays of Triangular Particles: Coupling Effects and Field Enhancements

M. Goncalves[1], T. Makaryan[2], G. Papageorgiou[3], U. Herr[3], and O. Marti[1]
[1]Ulm University - Inst. of Experimental Physics, Ulm, Germany
[2]Yerevan State University, Yerevan, Armenia
[3]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 ...

Going beyond Axisymmetry: 2.5D Vector Electromagnetics

Y.A. Urzhumov[1][,][2], N.I. Landy[1][,][2], C. Ciraci[2], D.R. Smith[1][,][2]
[1]Department of Electrical and Computer Engineering, Pratt School of Engineering, Duke University, Durham, NC, USA
[2]Center for Metamaterials and Integrated Plasmonics, Pratt School of Engineering, Duke University, Durham, NC, USA

Linear wave propagation through inhomogeneous structures of size R?? (Fig.1) is a computationally challenging problem, in particular when using finite element methods, due to the steep increase of the number of degrees of freedom as a function of R/?. Fortunately, when the geometry of the problem possesses symmetries, one may choose an appropriate basis in which the stiffness matrix of the ...

The Analysis of High Birefringence Photonic Crystal Fiber with Elliptical Air Holes Cladding

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 ...

Quick Search