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Full-Text Articles in Engineering

Spectral Characterization Of High-Speed Sers Fluctuations, Makayla Schmidt, Emily A. Farley, Marit A. Engevik, Alexandre G. Brolo, Nathan Lemke, Nathan Lindquist May 2024

Spectral Characterization Of High-Speed Sers Fluctuations, Makayla Schmidt, Emily A. Farley, Marit A. Engevik, Alexandre G. Brolo, Nathan Lemke, Nathan Lindquist

Science Symposium

The concept of plasmonic “hotspots” is central to the broad field of nanophotonics. In surface-enhanced Raman scattering (SERS), hotspots can increase Raman scattering efficiency by orders of magnitude. Hotspot dimensions may range from a few nanometers down to the atomic scale and are able to generate SERS signals from single molecules. However, these single-molecule SERS signals often show significant fluctuations, and the concept of intense, localized, yet static hotspots has come into question. Recent experiments have shown these SERS intensity fluctuations (SIFs) to occur over an extremely wide range of timescales, from seconds to micro-seconds, due to the various physical …


Developing Optical Devices And Projects For Teaching Engineering, Nathan D. Lemke, John Mccauley, Tristan E. Noble, Grace Riermann, Ellesa St. George, Nathan C. Lindquist, Keith R. Stein, Karen Irene Rogers Aug 2022

Developing Optical Devices And Projects For Teaching Engineering, Nathan D. Lemke, John Mccauley, Tristan E. Noble, Grace Riermann, Ellesa St. George, Nathan C. Lindquist, Keith R. Stein, Karen Irene Rogers

Physics and Engineering Faculty Publications

We are creating a suite of tools and techniques based on optics to be used for teaching a variety of engineering topics. Each tool is intended for non-expert use and without the need for high-end equipment such as vibration-free optical tables. Here we report progress on three such tools: image-plane digital holography for measuring mechanical deformation; schlieren imaging of convective flows using a smart phone; and a simple optical communication protocol using LabVIEW. We will present the designs of the tools and preliminary results from teaching engineering labs and projects with these tools. Specific courses impacted to date include Fluid …


Measurement Of Optical Rubidium Clock Frequency Spanning 65 Days, Nathan D. Lemke, Kyle W. Martin, River Beard, Benjamin K. Stuhl, Andrew J. Metcalf, John D. Elgin Mar 2022

Measurement Of Optical Rubidium Clock Frequency Spanning 65 Days, Nathan D. Lemke, Kyle W. Martin, River Beard, Benjamin K. Stuhl, Andrew J. Metcalf, John D. Elgin

Physics and Engineering Faculty Publications

Optical clocks are emerging as next-generation timekeeping devices with technological and scientific use cases. Simplified atomic sources such as vapor cells may offer a straightforward path to field use, but suffer from long-term frequency drifts and environmental sensitivities. Here, we measure a laboratory optical clock based on warm rubidium atoms and find low levels of drift on the month-long timescale. We observe and quantify helium contamination inside the glass vapor cell by gradually removing the helium via a vacuum apparatus. We quantify a drift rate of 4 x 10-15, a 10 day Allan deviation less than 5 x …


Erratum: Search For Heavy Higgs Bosons Decaying To A Top Quark Pair In Proton-Proton Collisions At S = 13 Tev (Journal Of High Energy Physics, (2020), 2020, 4, (171), 10.1007/Jhep04(2020)171), The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, W. Adam, F. Ambrogi, T. Bergauer, Julie M. Hogan Mar 2022

Erratum: Search For Heavy Higgs Bosons Decaying To A Top Quark Pair In Proton-Proton Collisions At S = 13 Tev (Journal Of High Energy Physics, (2020), 2020, 4, (171), 10.1007/Jhep04(2020)171), The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, W. Adam, F. Ambrogi, T. Bergauer, Julie M. Hogan

Physics and Engineering Faculty Publications

In figure 7 of the original publication, the label of the y axis should have been (Formula presented.)”. The corrected version is shown in figure 1. Accordingly, the text pointing to the figure should read “figure 7 shows scans of (Formula presented.) for this hypothesis, as a function of the coupling modifier gAtt-”.


Measurement Of W±Γ Differential Cross Sections In Proton-Proton Collisions At S =13 Tev And Effective Field Theory Constraints, The Cms Collaboration, A. Tumasyan, W. Adam, J. W. Andrejkovic, T. Bergauer, S. Chatterjee, Julie M. Hogan Mar 2022

Measurement Of W±Γ Differential Cross Sections In Proton-Proton Collisions At S =13 Tev And Effective Field Theory Constraints, The Cms Collaboration, A. Tumasyan, W. Adam, J. W. Andrejkovic, T. Bergauer, S. Chatterjee, Julie M. Hogan

Physics and Engineering Faculty Publications

Differential cross section measurements of W±γ production in proton-proton collisions at s=13 TeV are presented. The data set used in this study was collected with the CMS detector at the CERN LHC in 2016-2018 with an integrated luminosity of 138 fb-1. Candidate events containing an electron or muon, a photon, and missing transverse momentum are selected. The measurements are compared with standard model predictions computed at next-to-leading and next-to-next-to-leading orders in perturbative quantum chromodynamics. Constraints on the presence of TeV-scale new physics affecting the WWγ vertex are determined within an effective field theory framework, focusing on the O3W operator. A …


3d-Printable And Open-Source Modular Smartphone Visible Spectrophotometer, Brandon Winters, Nick Banfield, Cassandra Dixon, Anna Swensen, Dakota Holman, Braxton Fillbrown Oct 2021

3d-Printable And Open-Source Modular Smartphone Visible Spectrophotometer, Brandon Winters, Nick Banfield, Cassandra Dixon, Anna Swensen, Dakota Holman, Braxton Fillbrown

Chemistry Faculty Publications

The past four decades have brought significant and increasingly rapid changes to the world of instrument design, fabrication, and availability due to the emergence of 3D printing, open-source code and equipment, and low-cost electronics. These, along with other technological advances represent a nexus in time ripe for the wide-spread production and availability of low-cost sophisticated scientific equipment. To that end, the design of a 3D printable and open-source, modular spectrometer is described. This specific instrument is distinctly different from others that have been reported in recent years in that it was designed outside of the “black box” paradigm of …


Search For Bottom-Type, Vectorlike Quark Pair Production In A Fully Hadronic Final State In Proton-Proton Collisions At S =13 Tev, The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, W. Adam, F. Ambrogi, T. Bergauer, Julie M. Hogan, S Johnson Dec 2020

Search For Bottom-Type, Vectorlike Quark Pair Production In A Fully Hadronic Final State In Proton-Proton Collisions At S =13 Tev, The Cms Collaboration, A. M. Sirunyan, A. Tumasyan, W. Adam, F. Ambrogi, T. Bergauer, Julie M. Hogan, S Johnson

Physics and Engineering Faculty Publications

A search is described for the production of a pair of bottom-type vectorlike quarks (VLQs), each decaying into a b or b¯ quark and either a Higgs or a Z boson, with a mass greater than 1000 GeV. The analysis is based on data from proton-proton collisions at a 13 TeV center-of-mass energy recorded at the CERN LHC, corresponding to a total integrated luminosity of 137 fb-1. As the predominant decay modes of the Higgs and Z bosons are to a pair of quarks, the analysis focuses on final states consisting of jets resulting from the six quarks produced in …


Developing A Portable, Smartphone-Based Schlieren Imaging System, Grace Riermann, Keith R. Stein Oct 2020

Developing A Portable, Smartphone-Based Schlieren Imaging System, Grace Riermann, Keith R. Stein

Honors Student Works

Schlieren imaging is a technique for visualizing fluid flows that are characterized by spatial variations in density or refractive index. Because schlieren imaging is commonly performed with expensive equipment in a lab setting, we sought cost efficiency, accessibility, and ease of fabrication by designing a portable, smartphone-based system.


Digital Plasmonic Holography, Joseph W. Nelson, Greta R. Knefelkamp, Alexandre G. Brolo, Nathan C. Lindquist Dec 2018

Digital Plasmonic Holography, Joseph W. Nelson, Greta R. Knefelkamp, Alexandre G. Brolo, Nathan C. Lindquist

Physics and Engineering Faculty Publications

We demonstrate digital plasmonic holography for direct in-plane imaging with propagating surface-plasmon waves. Imaging with surface plasmons suffers from the lack of simple in-plane lenses and mirrors. Lens-less digital holography techniques, however, rely on digitally decoding an interference pattern between a reference wave and an object wave. With far-field diffractive optics, this decoding scheme provides a full recording, i.e., a hologram, of the amplitude and phase of the object wave, giving three-dimensional information from a two-dimensional recording. For plasmonics, only a one-dimensional recording is needed, and both the phase and amplitude of the propagating plasmons can be extracted for high-resolution …


3d Printable Optomechanical Cage System With Enclosure, Brandon Winters, David Shepler Apr 2018

3d Printable Optomechanical Cage System With Enclosure, Brandon Winters, David Shepler

Chemistry Faculty Publications

The advent of the computer-age in the mid to late 20th century brought the development of sophisticated scientific equipment for myriad chemical analyses. The field of spectroscopy alone has seen significant advances in data collection, processing, and analysis due principally to the incorporation of microprocessors. While it is clear computers have revolutionized the field of instrumental chemical analysis their impact is pervasive through every segment of our lives. From word processing, data management, and Computer Aided Design in our work environments to social media, crowd funding, and digital news at home, technology is everywhere. This work seeks to incorporate the …


Cooking Up The Optimal Baking Algorithm, Tony Burand, Michael Tetzlaff, Jacob Smith May 2013

Cooking Up The Optimal Baking Algorithm, Tony Burand, Michael Tetzlaff, Jacob Smith

Math and Computer Science Student Works

Many conventional rectangular baking pans have a problem in that they bake the corners of the batter faster than the rest of the pan. Circular baking pans eliminate this problem, but take up more space in the oven. We propose a solution that given weights for baking consistency and space efficiency based on the importance of each will provide the optimal baking pan shape. We have come up with an algorithm for sorting the pans of area A effectively and formed a model that describes the heat flow into the pan as well as the baking mix itself. The model …


Cooking Up The Optimal Baking Algorithm, Tony Burand, Michael Tetzlaff, Jacob Smith May 2013

Cooking Up The Optimal Baking Algorithm, Tony Burand, Michael Tetzlaff, Jacob Smith

Colloquy Undergraduate Research Journal

Many conventional rectangular baking pans have a problem in that they bake the corners of the batter faster than the rest of the pan. Circular baking pans eliminate this problem, but take up more space in the oven. We propose a solution that given weights for baking consistency and space efficiency based on the importance of each will provide the optimal baking pan shape. We have come up with an algorithm for sorting the pans of area A effectively and formed a model that describes the heat flow into the pan as well as the baking mix itself. The model …