Aqui você encontrará apresentações realizadas nas Conferências de Usuários COMSOL de todo o mundo. As apresentações englobam pesquisas e produtos inovadores feitas por engenheiros e cientistas usando o COMSOL Multiphysics. Os tópicos abrangem uma grande gama de indústrias e aplicações, como elétrica, mecânica, escoamento e química. Use a função de busca "Quick Search" para encontrar apresentações na sua área de interesse.

Electromagnetic Well Logs Simulated with the COMSOL® RF Module on a Cluster - new

D. Swaminathan[1], G. Minerbo[1], K. Pathak[1]
[1]Drilling and Production Group, Schlumberger, Houston, TX, USA

Introduction Computer simulations are widely used for the interpretation and inversion of electromagnetic measurements in well logging. Until recently, simulated logs have been computed with approximate 1D or 2D models. By using the COMSOL® RF Module installed on a cluster, we show that a full 3D finite-element simulated log can be obtained within an acceptable turnaround time. Use of ...

Heating of Metal Nanoparticles on Absorbing Substrates

L. Bergamini [1], O. Muskens [2], N. Zabala [1], J. Aizpurua [3]
[1] UPV/EHU, Bilbao, Spain; Materials Physics Center and CSIC-UPV/EHU, Donostia-San Sebastian, Spain; Donostia International Physics Center, Donostia-San Sebastian, Spain
[2] University of Southampton, Southampton, UK
[3] Materials Physics Center and CSIC-UPV/EHU, Donostia-San Sebastian, Spain; Donostia International Physics Center, Donostia-San Sebastian, Spain

It is well-known that metal nanoparticles (NPs) excited at the plasmon frequency not only exhibit peculiar optical properties (e.g., a peak in the extinction spectrum, an enhanced electromagnetic near-filed) but also heat up [1]. This phenomenon is highly investigated for medical applications, but it can be exploited also for the realization of optical devices. In our study we use COMSOL ...

Scattering of mm-Waves by Turbulent Structures in Magnetically Confined Fusion Plasmas

O. Chellaï [1], S. Alberti [1], I. Furno [1], T. Goodman [1], M. Baquero [1]
[1] Centre de Recherches en Physique des Plasmas, Ecole Polytechnique Fédérale de Lausanne, Suisse

In magnetically confined fusion devices, electron cyclotron resonance heating (80-170 GHz) is characterized by a local RF-power deposition at the electron cyclotron resonance [1]. A mm-wave RF Gaussian beam is launched from a dedicated antenna and propagates through the highly turbulent scrape-off layer (SOL) at the edge of the confined plasma. Turbulence in the SOL is characterized by ...

Analysis of a Prototype MRI Hybrid Birdcage RF Coil with Uncertainty Quantification (*)

J. T. Fong [1],
[1] National Institute of Standards & Technology, Gaithersbug, MD, USA

1. INTRODUCTION. In a magnetic resonance imaging (MRI) system (see Fig. 1), it is necessary to excite the nuclei of a patient into coherent precession for imaging. This requires coupling between the nuclei and a source of radio frequency (RF) power (the transmitter). To receive a meaningful signal, one also needs to couple the nuclei to an external circuitry (the receiver). These two ...

Plasmonic Properties of Bimetal Nanoshell Cylinders and Spheres

K. Ehrhold[1], S. Christiansen[1,2], and U. Gösele[1]
[1]Max Planck Institute of Microstructure Physics, Halle, Germany,
[2]Institute of Photonic Technology, Jena, Germany

Plasmonics is a new branch of the fascinating field of photonics and develops concepts to quench light beyond the diffraction limit and enhance electromagnetic fields. These enhancements occur in metals as localized surface plasmon polaritons (LSP) a coupling of the surface density oscillations of the electron gas to the incident light. With threedimensional nano-structures of coinage metals ...

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. ...

Numerical Optimization Technique for the Optimal Design of the Surface Plasmon Grating Coupler

C. Caiseda[1], V. Aksyuk[2], I. Griva[3]
[1]Inter American University of Puerto Rico, Bayamon, PR, USA
[2]National Institute of Standards and Technology, Gaithersburg, MD, USA
[3]George Mason University, Fairfax, VA, USA

The optimal design of the grating coupler for surface plasmon generation is revisited for its interdisciplinary importance in the efficient use of energy, and the strong dependence of the energy convergence rate of the system on the design. This work contributes a comprehensive gradient based numerical optimization technique to optimize both geometry of the grating and parameters of the ...

Electromagnetic Wave Analysis of Wave And Shielded Stripline

S. Singh[1], A. Marwaha[1]
[1]Department of Electronics and Communication Engineering, Sant Longowal Institute of Engineering Technology Longowal, Punjab, India

Electromagnetic wave analysis of waveguide has been done in this paper with the help of Finite Element Method (FEM) based COMSOL Multiphysics. The design is further extended by placing conductor on a dielectric slab included in the waveguide to form a shielded microstrip transmission line. The simulated models are analyzed to determine the wave propagation characteristics. The validation is ...

Low Cost All Optical Swept Source for Optical Communication Applications

J. T. Andrews[1], S. Chaurasiya[1], O. P. Chaudhary[1], D. Agarwal[1]
[1]National MEMS Design, Department of Applied Physics, Shri G S Institute of Technology & Science, Indore Madhya Pradesh, India

By introducing a periodic modulation in a waveguide, it is possible to create an interaction between forward-traveling and backward-traveling modes of an optical waveguide. Bragg grating may be a one dimensional diffraction grating which diffracts light from the forward-traveling mode into the backward traveling mode. Since the Bragg grating reflects at the wavelength for which it is ...

Chiral surface plasmon polaritons on metallic nanowires

S. Zhang
Institute of Physics CAS
Beijing
China

Chiral SPPs can be generated by linearly polarized light incident at the end of a nanowire, exciting a coherent superposition of three specific nanowire waveguide modes. Chirality is preserved in the emitted photons, creating a subwavelength ¼ wave plate.