R. Kumar, P. Singh
Bhabha Atomic Research Center, Trombay, Mumbai, India
High-power couplers working at 350 MHz for particle accelerator cavities are presently under development in the LEHIPA project at BARC. It is important to analyze RF losses on conducting surfaces and resulting thermal profiles. COMSOL Multiphysics® is used to study these coupled RF-thermal effects and estimate cooling requirements for these couplers. The RF loss on the copper conductors and ...
A. Leggieri, F. Di Paolo, D. Passi
University of Rome "Tor Vergata" - Department of Electronic Engineering, Rome, Italy
This paper describes the Virtual Prototyping based on a COMSOL Multiphysics® simulation for a novel Microwave Fin Taper (FT) Spatial Power Combiner (SPC) Amplifier. The analyzed system is waveguide (WG) based, and uses FT Probes to convert the energy of a rectangular WG EM fundamental mode to a Microstrip Transmission Line TEM mode, in order to be amplified by a Solid State Power ...
K. D. Donda , R. Kumar , H. B. Pandya ,
 Gujarat Technological University , Gandhinagar, India
 ITER-India (Institute for Plasma Research), Gandhinagar,India
Vacuum window is required in the millimeter wave transmission line in ITER*. It is to be designed to minimize the microwave reflection while keeping a robust and safe approach to meet the requirements. We have studied transmission characteristics of various dielectric materials over D-band frequency range (110-170 GHz) using RF Module of COMSOL Multiphysics®. Purpose of this study is to choose ...
刘小璐 , 汪滢莹 , 田翠萍 ,
 北京工业大学， 北京，中国
空芯光子晶体光纤（HC-PCFs）具有不同于传统光纤的带隙导光机制，在光通信系统、高功率激光器、工业制造和生物医疗等许多领域有广阔的应用前景。随着光纤拉制技术的不断进步，不同纤芯结构的 HC-PCFs 出现并带来了更好的光传输特性（图1）。通过设计新的纤芯形状，并运用 COMSOL Multiphysics® 中的 RF 模块进行仿真，可以研究各种纤芯 HC-PCFs 的模式（图2）、泄漏损耗（图3）和波导色散（图4）等特性。结果表明：设计的内凹圆化形纤芯 HC-PCFs 比传统的正十二边形纤芯 HC-PCFs 有更低的泄漏损耗和波导色散，而设计的内凹直线形纤芯 HC-PCFs 有很低的泄漏损耗和大的波导色散。新设计的纤芯结构未来可用于大容量光通信、光孤子传输以及色散补偿等应用中。
吴强 , 潘崇佩 , 张琦 ,
“极化激元”是固体物理学中的重要概念，泛指各种极性元激发与光子的耦合。其中，声子极化激元是指晶格振动的声子与电磁场中的光子相互耦合的一种极化激元波。使用飞秒光在铁电晶体铌酸锂中通过光学非线性效应可产生声子极化激元，其频率位于太赫兹波段，在晶格的振动弛豫、太赫兹光谱、与介观微结构作用等领域已有广泛应用。 声子极化激元涉及电磁场和晶格场的耦合问题，其形式满足黄昆方程。我们使用 COMSOL Multiphysics® 的多物理场（偏微分方程组以及射频模块）模拟了块状铌酸锂晶体中产生声子极化激元波的产生和传输。 铌酸锂晶体作为太赫兹应用的集成化平台，可通过在平板波导上引入微结构实现对太赫兹波的调控。诸多手段中，太赫兹天线作为电磁场的传播场与局域场转换的关键部件，对太赫兹通信和太赫兹光谱等领域都有不可替代的作用。基于这一点，我们设计了一种尖端相对的棒状天线结构，使用 COMSOL ...
M. Awida ,
 Fermi National Particle Accelerator Laboratory, Warrenville, IL, USA
Particle accelerator technology evolves gradually towards improving reliability and efficiency of the accelerator machines, which would reduce their cost for current applications and even make them more accessible to new industrial applications. RF cavities are utilized in particle accelerator machines to propel the particle beam by properly coupling the energy from RF sources to the particle ...
M. Csete , A. Szenes , G. Szekeres , B. Banhelyi , T. Csendes , G. Szabo ,
 Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary
 Institute of Informatics, University of Szeged, Szeged, Hungary
Introduction: Single-photon detectors capable of ensuring high fidelity read-out of quantum information delivered via photons of specific polarization are crucial in QIP . Our previous studies have shown that different types of one dimensional plasmonic structures enhance the absorptance of p-polarized light [2, 3]. The purpose of present study was to optimize four different types of ...
Self-Consistent Modeling of Thin Conducting Wires and Their Interaction with the Surrounding Electromagnetic Field
ABB AB, Corporate Research, Västerås, Sweden
It is demonstrated how the RF Module of COMSOL Multiphysics® can be used to approximately model thin conducting wires or cables and how they interact with a surrounding electromagnetic field. Despite being non-stringent the method can reasonably well predict currents induced by an applied electromagnetic field in wires, and networks of wires, as well as fields radiated from current-carrying ...
M. Gonçalves, O. Marti
Ulm University - Inst. of Experimental Physics, Ulm, Germany
Plasmonic resonances arising in gold nanoparticles lead to strongly localized near-field enhancements. These enhancements generate strong field gradients that can be exploited in particle trapping. On the other hand plasmonic resonances lead to enhanced absorption and heat generation. Gold nanoparticles have been used to kill cancer cells based on plasmonic heating. We have investigated the ...
李学识 , 郑李娟 ,
A patch antenna based on metamaterials of composite split-ring-resonators (CSRRs) and strip gaps is designed with COMSOL Multiphysics® software. The antenna is constructed by using CSRR structures in forms of circular rings on the patch and employing strip gaps on the ground plane. The signal is fed by a common microstrip line that connects the patch and the input port. The antenna is based on a ...