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.

太赫兹声子极化激元的产生及与金属天线的相互作用

吴强 [1], 潘崇佩 [1], 张琦 [1],
[1] 南开大学,天津,中国

“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 ...

Product Design of Macro Optical Clocking by Ray Optics

V. Vinothkumar[1], R. C. Thiagarajan [1],
[1] ATOA Scientific Technologies Pvt Ltd, Bangalore, India.

Optical cloaking was considered as fictional. Recent developments shows that macro scale optical cloaking is practical and functional. Brief review of ray optics based macro optical cloaking concepts are given. COMSOL Multiphysics® software simulations of cloaking devices are detailed. The geometric optics principles used to develop cloak for hiding objects are given. Invisibility of both the ...

Dual Phononic And Photonic Band Gaps In A Periodic Array Of Pillars Deposited On A Membrane

Y. Pennec, Y. El Hassouani, C. Li, B.D. Rouhani, E.H. El Boudouti, H. Larabi, and A. Akjouj
Institut d’Electronique, de Microélectronique et de Nanotechnologie, Université de Lille, Villeneuve d’Ascq, France

Phononic crystals are a class of materials that exhibit periodic variations in their density and elastic properties. Such crystals modify the propagation of acoustic waves and prohibit the propagation of sound for frequencies within the band gap. We discuss the simultaneous existence of phononic and photonic band gaps in a periodic array of silicon pillars deposited on a homogeneous SiO2 ...

Modeling Plasmonic Structure Integrated Single-Photon Detectors to Maximize Polarization Contrast

M. Csete [1], A. Szenes [1], G. Szekeres [1], B. Banhelyi [2], T. Csendes [2], G. Szabo [1],
[1] Department of Optics and Quantum Electronics, University of Szeged, Szeged, Hungary
[2] 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 [1]. 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 ...

Modeling of III-Nitride Quantum Wells with Arbitrary Crystallographic Orientation for Nitride-Based Photonics

M. Kisin, R. Brown, and H. El-Ghoroury

Ostendo Technologies, Inc., Carlsbad, CA, USA

A program for self-consistent modeling of electron-hole energy spectrum and space-charge distribution in III-nitride based quantum well (QW) structures has been developed. The model takes into consideration full 6-band description of the valence band states, nonparabolicity of the electron spectrum, quantum confinement of electrons and holes, strain induced modifications of the band structure, ...

Investigation of Ablation of a Copper Surface Caused by 220 Nanosecond Laser Pulse

M. Dillmann [1], B. Braun [1], M. Kottcke [1],
[1] Technische Hochschule Georg-Simon-Ohm, Nuernberg, Germany

This work investigates the ablation of a copper surface caused by the irradiation of a 220 ns laser pulse. Our focus is on the heat transport within the copper and takes the proceeding vaporization of surface substance into account. Our model ignores plasma dynamics and simulates the energy deposition using a surface heat source. The underlying absorption coefficient is made temperature ...

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 ...

Effects of Forced Airflow Cooling on Laser Beam Heating of Volume Bragg Gratings

S. Kaim[1], B. Anderson[1], G. Venus[1], J. Lumeau[1], V. Smirnov[2], B. Zeldovich[1], L. Glebov[1]
[1]CREOL, The College of Optics and Photonics, University of Central Florida, Orlando, FL, USA
[2]OptiGrate Corp, Oviedo, FL, USA

Forced airflow cooling of a Volume Bragg Grating heated by a laser beam was investigated by means of simulation with COMSOL Multiphysics®. In addition to air cooling of unrestricted airflow, a case of airflow directed by limiting glass plates was investigated. A number of temperature distributions and thermal deformations were obtained in simulations for different rates of airflows. Simulations ...

Forces and Heating in Plasmonic Particles

M. Gonçalves[1], O. Marti[1]
[1]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 ...

Direct and Indirect Coupling Mechanisms in a Chiral Plasmonic System

Zhongyue Zhang [1], Yuyan Chen [1],
[1] School of Physics and Information Technology, Shaanxi Normal University, Xi’an, China

手性等离激元纳米结构被广泛研究并用于生物监测、分析化学和负折射率介质方面。在该结构中直接耦合的机制已经在相关研究中被发现。我们提出由金膜分隔两个金纳米棒(TNMF)的结构(图1),并发现了间接耦合机制。 在 COMSOL Multiphysics® 中,射频电磁波,频域接口用于求解正弦时变电磁场分布,选此接口计算 TNMF 结构的光学响应。插值函数用来设置金的折射率;设置边界条件模拟周期性结构阵列。结果可通过端口2对端口1的响应获得,并可查看每个数据点的电场、电荷等分布。应用程序库中射频模块的“Plasmonic wire grating”教程是初始指导我们计算纳米结构的例子。 用软件模拟圆偏振光照射,得到透射曲线和圆二色性(CD)曲线(图2)。加入金膜的结构产生新模式2。通过 B-K 模型分析电荷分布(图3),发现模式1是直接耦合,模式2是间接耦合。对间接耦合模式,上 ...