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.

Modeling and Simulation of Silicon Optical MEMS Switches Controlled by Electrostatic Field

J. Golebiowski[1], S. Milcarz[1]
[1]Technical University of Lodz, Poland

The use of optical sensors in the industry is still growing. A transmission of signal from the sensors is mostly done by optical fibers. Switching the signals from optical paths may be done by using micromechanical silicon switches. The main advantage is an ability to transmit data from many sensors using different wavelengths, simultaneously minimizing optical power losses. A silicon beam with ...

Modelling Ultra-short Pulse Laser Ablation of Dielectric Materials Using multiple Rate Equations - new

P. Boerner[1], K. Wegener[1]
[1]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 ...

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 ...

Optical Trapping on Waveguides

O.G. Hellesø [1],
[1] University of Tromsø, Tromsø, Norway

On the surface of an optical waveguide, there is an evanescent field. The evanescent field decays fast and this steep gradient can be used to pull nano- and microparticles down towards the waveguide surface. Radiation forces will propel the particle forward along the waveguide. Trapping on an optical waveguide can be used to manipulate particles in a lab-on-a-chip system where optical methods ...

Doping Dependent I-V Characteristics of Single Silicon Nanowire

S. Mishra [1], S. K. Saxena [1], P. Yogi [1], P. R Sagdeo [1], R. Kumar [1],
[1] Indian Institute of Technology Indore, Indore, Madhya Pradesh, India

In the present work, we have studied the electron transport properties of single silicon nanowire using Semiconductor Module of COMSOLMultiphysics software. We construct a MSM (metal-semiconductor-metal) model where metal is selected as copper and semiconductor is taken as silicon. Silicon is doped with n-type impurity by increasing doping concentration. Further, the Schottky diodes formed at ...

AlGaInAs/InP Hexagonal Resonator Microlasers with a Center Hole

H. Weng [1], Y. Yang [1], B. Liu [1], X. Ma [1]
[1] Institute of Semiconductors, Chinese Academy of Science, Beijing, China

In the past decades, equilateral polygonal microcavity lasers with whispering-gallery modes (WGMs) have attracted great attentions due to their potential application in photonic-integrated circuits. Compared to the perfect microdisk without deformation, the polygonal microcavities such as triangle, square, hexagonal and octagonal can easily realize the light directional emission and single mode ...

Electromagnetic Analysis of Cloaking Metamaterial Structures

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

We study cylindrical and spherical shell structures that have cloaking material properties proposed by Pendry et al. We use 2D and 3D time-harmonic analysis to study the field distribution and power flow for various arrangements of these structures. We have shown that the COMSOL RF solver is well suited for the analysis of cloaking metamaterial structures If cloaking material properties can be ...

A Study of Distributed Feed-Back Fiber Laser Sensor for Aeronautical Applications Using COMSOL Multiphysics

I. Lancranjan[1], C. Gavrila[2], S. Miclos[3], and D. Savastru[3]
[1]Advanced Study Centre - National Institute for Aerospace Research Elie Carafoli, Bucharest, Romania
[2]Technical University of Civil Engineering Bucharest, Romania
[3]National Institute R&D of Optoelectronics, INOE 2000, Bucharest, Romania

Distributed Feedback Fiber Laser (DFB-FL) sensors are increasingly used in aeronautical applications. One of the newest such applications consists in detecting the “transition” zone between laminar and turbulent air flow upon the extrados surface of an aircraft wing. In this specific application DFB-FL are operated as air pressure sensors monitoring amplitude variations of ~1 Pa (laminar flow) ...

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 ...

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 ...