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Displaying 1 - 25 of 2511

Optical clock frequency ratios with uncertainty ? 3.2 * 10^-18

January 6, 2026
Author(s)
Alexander Aeppli, Willa Arthur-Dworschack, Kyle Beloy, Caitlin Berry, Tobias Bothwell, Angela Folz, Tara Fortier, Tanner Grogan, Youssef Hassan, Zoey Zimeng Hu, David Hume, Benjamin Hunt, Kyungtae Kim, Amanda Koepke, Dahyeon Lee, David Ray Leibrandt, Ben Lewis, Andrew Ludlow, Mason Marshall, Nicholas Nardelli, Harikesh Ranganath, Daniel Rodriguez Castillo, Jeffrey Sherman, Jacob Siegel, Suzanne Thornton, William Warfield, Jun Ye
We report high-precision frequency ratio measurements between optical atomic clocks based on 27Al+, 171Yb, and 87Sr. With total fractional uncertainties at or below 3.2 × 10−18, these measurements meet the milestone criteria for redefinition of the second

Detection of molecular hydrogen in a neutron beam lifetime experiment

December 12, 2025
Author(s)
Jimmy Caylor, Ripan Biswas, Bret Crawford, Maynard Dewey, Nadia Fomin, Geoffrey Greene, Shannon Hoogerheide, Jose Hungria-Negron, Hans Mumm, Jeffrey Nico, Daniel Valete, Fred Wietfeldt, Joseph Zuchegno
One method of determining the free neutron lifetime involves the absolute counting of neutrons and trapped decay protons. In such experiments, a cold neutron beam traverses a segmented proton trap inside a superconducting solenoid while the neutron flux is

Selecting the complexity of the Moore-Penrose pseudoinverse for emission ghost imaging

December 2, 2025
Author(s)
Kevin Coakley, Huaiyu Chen-Mayer, Bruce Ravel, Daniel Josell, Nikolai Klimov, Daniel Hussey
We reconstruct X-ray fluorescence signals produced by synchrotron X-rays. In our method, we select the complexity of a Moore-Penrose pseudoinverse by a data-driven method, and study how systematic errors affect results for simulated data.

A comparative study of time on Mars with lunar and terrestrial clocks

December 1, 2025
Author(s)
Neil Ashby, Bijunath Patla
As space exploration extends into cislunar space and further towards Mars, understanding the relativistic effects on clocks on Mars—particularly in relation to multi-body gravitational influences—becomes increasingly important for accurate clock

Compatibility of trapped ions and dielectrics at cryogenic temperatures

November 17, 2025
Author(s)
Margaret Bruff, Lindsay Sonderhouse, Kaitlyn David, Daniel Slichter, Dietrich Leibfried, Jules Stuart
We study the impact of an unshielded dielectric\textemdash here, a bare optical fiber\textemdash on a $^40}$Ca$^+}$ ion held several hundred $\mu$m away in a cryogenic surface electrode trap. We observe distance-dependent stray electric fields of up to a

Efficient production of sodium Bose-Einstein condensates in a hybrid trap

September 10, 2025
Author(s)
Ian Spielman, Stephen Eckel, Gretchen Campbell, Yanda Geng, Shouvikl Mukherjee, Swarnav Banik, Monica Gutierrez~Galan, Hector Sosa-Martinez, Madison Anderson
We describe an apparatus that efficiently produces $^23}$Na Bose-Einstein condensates (BECs) in a hybrid trap that combines a quadrupole magnetic field with a far-detuned optical dipole trap. Using a Bayesian optimization framework, we systematically

Topology and Kinetic Pathways of Colloidosome Assembly and Disassembly

September 4, 2025
Author(s)
Raymond Adkins, Joanna Robaszewski, Seungwoo Shin, Fridtjof Brauns, Leroy Jia, Ayantika Khanra, Prerna Sharma, Robert Pelcovits, Thomas Powers, Zvonimir Dogic
Liquid shells, such as lipid vesicles, emulsions, and soap bubbles, are ubiquitous throughout biology, engineered matter, and everyday life. Their creation or disintegration is defined by a singularity separating topologically distinct one-boundary

Accurate, precise pressure sensing with tethered optomechanics

August 28, 2025
Author(s)
Olivia Green, Yiliang Bao, John R. Lawall, Jason Gorman, Daniel Barker
We show that optomechanical pressure sensors with characterized density and thickness can achieve uncertainty as low as 1.1 % via comparison with a secondary pressure standard. The agreement between the secondary standard and our optomechanical sensors is

Direct detection of the ? 8.4 eV internal conversion energy of 229mTh embedded in a superconducting nanowire

August 25, 2025
Author(s)
Galen O'Neil, Kjeld Beeks, Eric Hudson, David Ray Leibrandt, Marion Mallweger, Sae Woo Nam, Sayan Patra, Gil Porat, Dileep Venkatarama Reddy, Thorsten Schumm, Stephen Schoun, Benedict Seiferle, Christian Schneider, Lars von der Wense, Peter Thirolf, Varun Verma, Jun Ye, Chuankun Zhang
We report on a direct measurement of the ∼ 8.4 eV nuclear excitation energy of the isomeric first excited state 229mTh via the internal conversion (IC) decay channel. Thermalized and mass-filtered recoiling 229mTh ions from 233U α decay are delivered to

Direct measurement of the 3P0 clock state natural lifetime in 87Sr

August 24, 2025
Author(s)
Kyle Beloy, Jonathan Dolde, Dhruva Ganapathy, Xin Zheng, Shuo Ma, Shimon Kolkowitz
Optical lattice clocks based on the narrow transition between (5s2)1S0 -(5s5p)3P0 levels in neutral strontium (Sr) are among the most precise and accurate measurement devices in existence. Although this transition is completely forbidden by selection rules

Ion Coulomb crystals: an exotic form of condensed matter

August 24, 2025
Author(s)
Giovanna Morigi, John Bollinger, Michael Drewsen, Daniel Podolsky, Efrat Shimshoni
Wigner crystals formed by laser-cooled ions in traps are unconventional condensed matter systems, characterized by interparticle distances of several micrometers and energy scales on the order of meV. Their crystalline structure emerges from the interplay

Quantum Vibro-Polaritonic Sensing

August 15, 2025
Author(s)
Peng Zheng, Stephen Semancik, Ishan Barman
Vibrational spectroscopies are pivotal in analytical methods and biomedical diagnostics owing to their singular ability to provide molecular specificity. Yet, they are intrinsically limited by weak light-matter interactions and their vulnerability to
Displaying 1 - 25 of 2511
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