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Search Publications by: William McGehee (Fed)

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Displaying 1 - 11 of 11

Next-Generation Chip-Scale Atomic Clocks

October 16, 2023
Author(s)
John Kitching, Matthew Hummon, William McGehee, Ying-Ju Wang, Susan Schima
We describe work toward the development of next-generation chip-scale atomic clocks, which combine small size, low power consumption and manufacturability with high frequency stability. The use of optical transitions in microfabricated vapor cells improves

A chip-scale atomic beam clock

June 13, 2023
Author(s)
Gabriela Martinez, Chao Li, Alexander Staron, John Kitching, Chandra Raman, William McGehee
We demonstrate a passively pumped, chip-scale atomic beam clock fabricated using a stack of silicon and glass wafers. The device could additionally serve as a platform for compact atom interferometers and other future quantum sensors.

Inhomogenous Light Shifts of Coherent Population Trapping Resonances

April 13, 2022
Author(s)
Juniper Pollock, Valera Yudin, Alexey Taichenachev, Maxim Basalaev, D Kovalenko, Azure Hansen, John Kitching, William McGehee
Coherent population trapping (CPT) in atomic vapors using all-optical interrogation has enabled the miniaturization of microwave atomic clocks. Light shifts induced by the CPT driving elds can impact the spectral pro le of CPT resonances and are a common

Magneto-optical trapping using planar optics

January 29, 2021
Author(s)
William McGehee, Wenqi Zhu, Daniel Barker, Daron Westly, Alexander Yulaev, Nikolai Klimov, Amit Agrawal, Stephen Eckel, Vladimir Aksyuk, Jabez J. McClelland
Laser-cooled atoms are a key component of many calibration-free measurement platforms— including clocks, gyroscopes, and gravimeters—and are a promising technology for quantum networking and quantum computing. The optics and vacuum hardware required to

Transport dynamics in a high-brightness magneto-optical-trap Li ion source

September 15, 2020
Author(s)
Jamie Gardner, William R. McGehee, Mark D. Stiles, Jabez J. McClelland
Laser-cooled gases offer an alternative to tip-based methods for generating high brightness ions for focused ion beam applications. These sources produce ions by photoionization of ultracold neutral atoms, where the narrow velocity distribution associated

Engineered Sulfur-MoS2-Graphene Heterostructure Cathodes for Diagnostics of Nanoscale Electrochemical Processes in High Energy Density Li-S Batteries

August 5, 2019
Author(s)
Vladimir P. Oleshko, William R. McGehee, Saya Takeuchi, Siyuan Zhang, Andrei A. Kolmakov, Jabez J. McClelland, Christopher L. Soles
Lithium-sulfur (Li-S) batteries have recently attracted enormous attention because of high theoretical specific energy (2600 Wh kg-1) and high specific capacity (1672 mAhg-1), as well as the low cost, natural abundance, and nontoxicity of elemental sulfur

Direct-write Lithiation of Silicon Using a Focused Ion Beam of Li+

July 8, 2019
Author(s)
William R. McGehee, Evgheni Strelcov, Vladimir P. Oleshko, Christopher L. Soles, Nikolai B. Zhitenev, Jabez J. McClelland
Electrochemical processes that govern the performance of lithium ion batteries involve numerous parallel reactions and interfacial phenomena that complicate the microscopic understanding of these systems. As a new way to study the behavior of ion transport

Characterization of a high-brightness, laser-cooled Li+ ion source

February 20, 2019
Author(s)
Jamie R. Gardner, William R. McGehee, Jabez J. McClelland
Ion sources based on laser cooling have recently provided new pathways to high-resolution microscopy, ion milling, and ion implantation. Here, we present the design and detailed characterization of Li-7 magneto-optical trap ion source (MOTIS) with a peak

Communication-Comparison of Nanoscale Focused Ion Beam and Electrochemical Lithiation in beta-Sn Microspheres

December 5, 2016
Author(s)
Saya Takeuchi, William R. McGehee, Jennifer L. Schaefer, Truman M. Wilson, Kevin A. Twedt, Christopher L. Soles, Vladimir P. Oleshko, Eddie H. Chang, Jabez J. McClelland
The development of Li focused ion beams (Li-FIB) enables controlled Li ion insertion into materials with nanoscale resolution. We take the first step toward establishing the relevance of the Li-FIB for studies of ion dynamics in electrochemically active