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.

Coupling Picosecond Terahertz Pulses to a Scanning Tunneling Microscope

P. H. Nguyen [1], C. Rathje [2], G. J. Hornig [1], V. Jelic [1], C. Ropers [2], F. A. Hegmann [1],
[1] University of Alberta, Edmonton, AB, Canada
[2] 4th Physical Institute, University of Göttingen, Göttingen, Germany

Probing ultrafast processes over subpicosecond and picosecond time scales provides fundamental insight into the nature of materials. We have experimentally demonstrated terahertz (THz)-pulse-induced tunneling in a scanning tunneling microscope (THz-STM) to image surfaces with simultaneous nanometer spatial resolution and subpicosecond time resolution [1]. However, the exact mechanism by which ...

A Study of Laser Doppler Anemometer Using COMSOL Multiphysics®

I. Lancranjan[1] and C. Gavrila[2]
[1]Advanced Study Centre, National Institute for Aerospace Research “Elie Carafoli”, Bucharest, Romania
[2]Technical University of Civil Engineering Bucharest, Bucharest, Romania

Laser anemometers based on application of Doppler Effect have been developed and are used in-flight, on aircrafts for measurement of air flow parameters, mainly its speed versus the airplane. The air speed measurements are vital for safe flights. The main basic idea of Doppler techniques consists in measuring the frequency of scattered light. In this paper, we propose a study of a laser Doppler ...

Optimal Design for the Grating Coupler of Surface Plasmons

Y. Huang

Mathematics Department, University of California, Los Angeles, CA, USA

We present an optimization procedure to optimize the maximum coupling of free space optical wave to surface plasmon. Shape derivative from shape sensitivity analysis is calculated, and the corresponding partial derivatives of the objective functional with respect to finite number of design variables are derived. An optimal design of the gratings to couple maximum amount of free space photon ...

Time-Resolved Optical Tomography in Preclinical Studies: Propagation of Excitation and Fluorescence Photons.

F. Nouizi[1], R. Chabrier[1], M. Torregrossa[2], and P. Poulet[1]
[1]Laboratoire d’Imagerie et de Neurosciences Cognitives, Straßbourg, France
[2]Laboratoire des Sciences de l'Image, de l'Informatique et de la Télédétection, France

We present time-resolved methods that rely on near-infrared photons to image the optical properties and distribution of fluorescent probes in small laboratory animals. The coupled diffusion equations of excitation and fluorescence photons in highly scattering tissues were solved using the three-dimensional Finite Element Method (FEM) provided by COMSOL. The computed results allowed to yield ...

Design for an Invisibility Cloak

T. Ochiai
Toyama Prefectural University
Japan

In order to design invisibility cloak, we use two different type of spaces: Physical space and Mathematical space. This paper is in Japanese.

Void Shape Evolution of Silicon: Level-Set Approach - new

C. Grau Turuelo[1], C. Breitkopf[1]
[1]Technische Universität Dresden, Dresden, Germany

The void shape evolution of silicon is a process driven mainly by surface diffusion which leads to a geometrical transformation of trenches etched in silicon wafers due to surface energy minimization. The temperature, the ambient gas and the annealing time affect the velocity of the process. The use of custom PDEs in COMSOL Multiphysics® software and the Level-Set method provide a good base ...

Full-Wave Analysis of Nanoscale Optical Trapping

E. Furlani, and A. Baev
The Institute for Lasers, Photonics and Biophotonics, University at Buffalo, Buffalo, NY, USA

Plasmonic-based optical trapping is in its infancy and growing rapidly. Research in this area will significantly advance fundamental understanding in fields such as nanophotonics and biophotonics. Novel plasmonic trapping structures and systems can be designed and optimized using the COMSOL RF solver.   We present a study of plasmonicbased optical trapping of neutral sub-wavelength ...

Finite Element Analysis of Integrated Circuit Interconnect Lines on Lossy Silicon Substrate

S. Musa[1], M. Sadiku[1], and A. Emam[2]

[1]Roy G. Perry College of Engineering, Prairie View A&M University, Prairie View, TX
[2]Information Systems Department, King Saud University, Riyadh, Saudi Arabia

The silicon substrate has a significant effect on the inductance parameter of a lossy interconnect line on an integrated circuit. It is essential to take this into account in determining the transmission line electrical parameters. In this paper, a new quasi-TEM capacitance and inductance analysis of multiconductor multilayer interconnects is successfully demonstrated using the finite element ...

Design de uma Fibra de Cristal Fotônico para a Propagação de Modos com Momento Angular Orbital

F. B. Mejía [1], M. F. V. de Almeida [1],
[1] Instituto Nacional de Telecomunicações - INATEL, Santa Rita do Sapucaí, MG, Brasil

Uma das formas de se conseguir a multiplexação modal de informações em uma fibra óptica é através do uso do momento angular orbital (OAM). Neste trabalho exploramos a riqueza estrutural das fibras de cristal fotônico (PCF) para aprimorar a transmissão de modos OAM. Usamos o RF Module do software COMSOL Multiphysics para calcular os modos de propagação de uma PCF. Então, através do Livelink™ for ...

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 ...