Systematic evaluation of an atomic clock at 2 × 10−18 total uncertainty
https://www.nature.com/articles/ncomms7896
https://arxiv.org/abs/1412.8261
Here we demonstrated operation of an atomic clock, with the highest (at that time) accuracy. This included full evaluation of all the systematic effects that limit the clock accuracy, with the major improvements being accurate monitoring of the temperature around the clock, and better characterization of the atomic transitions. An independent analysis of several of these systematic effects was the bulk of my undergraduate thesis
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http://www.npr.org/2014/11/03/361069820/new-clock-may-end-time-as-we-know-it
https://www.nbcnews.com/science/science-news/atomic-clock-wont-lose-second-15-billion-years-n346366
https://www.vox.com/2015/4/22/8468781/atomic-clock
Comparative Analysis of Satellite Aerodynamics and Its Application to Space-Object Identification
https://arc.aiaa.org/doi/abs/10.2514/1.A33482
In this work, we showed how accurate ground-based radar tracking of the debris generated in a satellite deployment as it falls back to earth, combined with high fidelity cross section modelling, allows rapid object identification. This allows users to identify which tracked objects are the satellite of interest (versus just space junk) more quickly.
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https://www.eurekalert.org/pub_releases/2013-09/uoca-css091113.php
http://www.parabolicarc.com/2013/09/28/dande-satellite-falcon-9-flight
High-resolution optical spectroscopy with a buffer-gas-cooled beam of BaH molecules
https://journals.aps.org/pra/abstract/10.1103/PhysRevA.96.022509
https://arxiv.org/abs/1705.00113
Here we perform the high accuracy measurements of level structure of BaH, as well as show it responds to magnetic fields. This was the first publication using the cold molecule source I built, and we were able to pin down all the information we needed to laser cool BaH.
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Broadband frequency comb generation in the near-visible using higher-order modes in silicon nitride microresonators
https://ieeexplore.ieee.org/abstract/document/8084389
We showed how a very small circle of silicon nitride, can be used to generate a frequency comb. This is a very cool type of laser, which has a lot of scientific and commercial applications, and we showed how it can be made using a very tiny footprint. I performed analysis characterizing the device to show it has the expected performance. They later used a similar technique, to make a frequency comb that runs on a AAA battery which is incredible. https://www.nature.com/articles/s41586-018-0598-9
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https://www.sciencedaily.com/releases/2018/10/181008141142.htm
A Fermi-degenerate three-dimensional optical lattice clock
https://science.sciencemag.org/content/358/6359/90
https://arxiv.org/abs/1702.01210
For this project we engineered atoms into a kind of quantum “crystal” to make an even more accurate atomic clock. The general problem is that when you have a lot of atoms in one place, the bump into each other, and this makes the clock less accurate. This crystal is a way of completely avoiding this problem, using some very “cool” quantum tricks made possible by working at incredibly low temperatures.
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Assignment of excited-state bond lengths using branching-ratio measurements: The BSigma state of BaH molecules
https://journals.aps.org/pra/abstract/10.1103/PhysRevA.100.022506
https://arxiv.org/abs/1904.07326
Here we repurposed some data I had collected on how BaH molecules emit and absorb light, to make a more accurate measurement for the size of the molecule. This was a novel use of the data and is a technique which could potentially be applied to a lot of other molecules.
Constraining domain wall dark matter with a network of superconducting gravimeters and LIGO
https://link.springer.com/article/10.1140/epjd/e2020-100632-0
https://arxiv.org/abs/1912.06703
This was a side project, where I realized that a certain type of dark matter will actually generate a signal we can look for using already existing data sets (instead of having to build a brand new experiment which takes a lot of money). I showed how this type of dark matter which is commonly looked for in my field, will actually ‘push’ objects around, meaning we can see it in gravitational acceleration measurement devices. It even pushes the mirrors that make up the LIGO gravitational wave detector. This allows us to data-mine two archived data sources to try and learn something new about what dark matter is without an expensive new equipment.
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https://www.sciencedaily.com/releases/2020/04/200409093957.htm
https://phys.org/news/2020-04-methods-dark-tiny-perturbations-fundamental.html
https://www.spacedaily.com/reports/Looking_for_dark_matter_999.html
Optical cycling, radiative deflection and laser cooling of barium monohydride (BaH)
https://arxiv.org/abs/2004.09570
This was the first demonstration of laser cooling, and optical control of hydride molecules. This very exciting because it is the first step towards making ultracold samples that we can study, and use as test beds for fundamental physics. We also hope that this will allow us to explore new ways to make ultracold samples, by breaking up the cold molecules into their atomic constituents.
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