Keynote Video: Improving Synchrotron Light Sources with Applications
Bridget Paulus December 19, 2018
When it comes to synchrotron light sources, brighter is better. By using bright beams in their accelerator, researchers at the Advanced Photon Source (APS) synchrotron facility can efficiently gather detailed data. In collaboration with APS engineers, Nicholas Goldring of RadiaSoft LLC creates and distributes simulation applications for designing vacuum chambers relevant to the APS. Below, find a video recording and summary of his keynote talk from the COMSOL Conference 2018 Boston.
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Brianne Christopher August 14, 2018
If you ever visit the extravagant dome within St. Paul’s Cathedral in London, be careful what you say. As Lord Rayleigh discovered circa 1878, the vaulted structure exhibits an interesting acoustics phenomenon: Whispers from one part of the dome can be clearly heard in other areas. Rayleigh called the effect a “whispering gallery”. Surprisingly, you can observe a similar effect in another field of science entirely: light waves traveling in an optical ring resonator.
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Yosuke Mizuyama June 26, 2018
In a previous blog post, we discussed the paraxial Gaussian beam formula. Today, we’ll talk about a more accurate formulation for Gaussian beams, available as of version 5.3a of the COMSOL® software. This formulation based on a plane wave expansion can handle nonparaxial Gaussian beams more accurately than the conventional paraxial formulation.
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Brianne Christopher May 9, 2018
During his life, John Scott Russell chased his passion for science — literally. While watching horses pull a boat through a shallow canal, he noticed a wave behaving strangely and followed it for one or two miles on horseback. For the rest of his life, he continued to chase this wave (which he called the “wave of translation”) figuratively, persevering even when his theories were ridiculed by scientists. Did Scott Russell ever catch up to his wave?
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Uttam Pal April 6, 2018
In 1875, John Kerr placed current-carrying coils in holes on either side of a glass slab, which created an electric field. After a polarized beam of light passed through the slab, he noticed that the polarization was different. This difference is related to the change in the glass’ refractive index, which is proportional to the square of the electric field — a phenomenon called the Kerr effect. See how to model this effect and other linear and nonlinear phenomena.
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Yosuke Mizuyama January 8, 2018
In the wave optics field, it is difficult to simulate large optical systems in a way that rigorously solves Maxwell’s equation. This is because the waves that appear in the system need to be resolved by a sufficiently fine mesh. The beam envelopes method in the COMSOL Multiphysics® software is one option for this purpose. In this blog post, we discuss how to use the Electromagnetic Waves, Beam Envelopes interface and handle its restrictions.
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Uttam Pal December 4, 2017
On a bright evening in 1669, Professor Erasmus Bartholinus looked through a piece of an Icelandic calcite crystal he had placed onto a bench. He observed when he covered text on the bench with the stone, it appeared as a double image. The observed optical phenomenon, called birefringence, involves a beam of light that splits into two parallel beams while emerging out of a crystal. Here, we demonstrate a modeling approach for this effect.
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Uttam Pal September 19, 2017
In 1870, an audience watched as a stage was set with two buckets, one on top of the other. Due to a small hole in the upper bucket, water poured into the lower bucket, bending as it did so. To the audience’s amazement, sunlight followed the bend of water — a phenomenon later termed total internal reflection. The performer on stage, John Tyndall, was one of the many scientists who tried to control the most visible form of energy: light.
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Walter Frei June 6, 2017
Whenever light is incident on a dielectric material, like glass, part of the light is transmitted while another part is reflected. Sometimes, we add a metal coating, such as gold, which alters the transmittance and reflectance as well as leads to some absorption of light. The dielectric surface and the metal coating also often have some random variations in height and thickness. In this blog post, we will introduce and develop a computational model for this situation.
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Bridget Cunningham April 17, 2017
Optical fibers that deliver midinfrared wavelengths are in high demand for a range of relative applications. As infrared transparent materials, semiconductors are useful for this purpose when combined with silica, helping to realize a new generation of midinfrared fiber optics. While important to performance, measuring the optical losses of such structures can be challenging experimentally because of time and costs. Simulation enables us to efficiently model this behavior for varying wavelengths and fiber geometries and identify strategies to reduce losses.
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Yosuke Mizuyama February 27, 2017
We previously learned how to calculate the Fourier transform of a rectangular aperture in a Fraunhofer diffraction model in the COMSOL Multiphysics® software. In that example, the aperture was given as an analytical function. The procedure is a bit different if the source data for the Fourier transformation is a computed solution. In this blog post, we will learn how to implement the Fourier transformation for computed solutions with an electromagnetic simulation of a Fresnel lens.
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