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Search Publications

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Displaying 1 - 25 of 2430

Modulated Laser Thermal Interrogation (MLTI): A Novel In Situ Metal Powder Evaluation Technique for Laser Powder Bed Fusion

March 1, 2025
Author(s)
Sina Ghadi, Xiaobo Chen, Nicholas Tomasello, Nicholas Derimow, Srikanth Rangarajan, Guangwen Zhou, Scott Schiffres
Assessment of metal powders in powder bed additive manufacturing is crucial, as the quality of the powders significantly impacts the final printed parts. This study introduces a novel technique to characterize metal powders by analyzing changes in their

Kolmogorov turbulence in atomic Bose-Einstein condensates

February 25, 2025
Author(s)
Ian Spielman, Mingshu Zhao, Junheng Tao
We investigated turbulence in atomic Bose-Einstein condensates (BECs) using a minimally destructive, impurity injection technique analogous to particle image velocimetry in conventional fluids. Our approach transfers small regions of the BEC into a

Measurement resolution enhanced coherence for lattice fermions

February 25, 2025
Author(s)
Ian Spielman, Hilary Hurst, Yik Teoh
Weak measurement enables the extraction of targeted information from a quantum system while minimizing decoherence due to measurement backaction. However, in many-body quantum systems backaction can have unexpected effects on wavefunction collapse. We

System Vicarious Calibration for climate and global long-term operational ocean color applications

February 25, 2025
Author(s)
Giuseppe Zibordi, B. Carol Johnson, Ewa Kwiatkowska, Kenneth Voss, David Antoine, Sean William Bailey, Andrew Barnard, Brian Barnes, Agnieszka Bialek, Shuguo Chen, Susanne Craig, Constant Mazeran, FREDERIC MELIN, Jee-Eun Min, Hiroshi Murakami, Menghua Wang
System Vicarious Calibration (SVC) enhances the accuracy of satellite ocean color radiometric data products by removing the bias due to the intrinsic inaccuracies affecting both the responsivity of the space sensor and the correction for the atmospheric

Effect of ''glancing'' collisions in the cold atom vacuum standard

February 12, 2025
Author(s)
Stephen Eckel, Daniel Barker, James A. Fedchak, Jacek Klos, Julia Scherschligt, Eite Tiesinga
We theoretically investigate the effect of "glancing" collisions on the ultra-high-vacuum pressure readings of the cold-atom vacuum standard (CAVS), based on either ultracold $^7$Li or $^87}$Rb atoms. Here, glancing collisions are those collisions between

Cryogenic photonic resonator with 10-17/s drift

February 11, 2025
Author(s)
Wei Zhang, William Milner, Jun Ye, Scott Papp
Thermal noise is the predominant instability in the provision of ultrastable laser frequency by reference to a cavity. Reducing the thermal-noise limit of a cavity means either making it larger to spread thermal fluctuations, reducing the sensitivity of

Nanophotonic oscillators for laser conversion beyond an octave

February 11, 2025
Author(s)
Grant Brodnik, Haixin Liu, David Carlson, Jennifer Black, Scott Papp
Many uses of lasers place the highest importance on access to specific wavelength bands. For example, mobilizing optical-atomic clocks for a leap in sensing requires compact lasers at frequencies spread across the visible and near infrared. Integrated

Photonic Millimeter-wave Generation Beyond the Cavity Thermal Limit

February 11, 2025
Author(s)
William Groman, Igor Kudelin, Takuma Nakamura, Yifan Liu, Charles McLemore, Franklyn Quinlan, Scott Diddams, Dahyeon Lee, Megan Kelleher, Joel Guo, Warren Jin, John Bowers
With the next generation of telecommunications and radar/navigation upon us, moving from the microwave to the higher bandwidth, millimeter-wave domain has become ever relevant. Simultaneously, the burgeoning field of photonic integrated chips has yielded a

The bandgap-detuned excitation regime in photonic-crystal resonators

February 11, 2025
Author(s)
Yan Jin, Erwan Lucas, Jizhao Zang, Travis Briles, Ivan Dickson, David Carlson, Scott Papp
Control of nonlinear interactions in microresonators enhances access to classical and quantum field states across nearly limitless bandwidth. A recent innovation has been to leverage coherent scattering of the intraresonator pump as a control of group

International Comparison CCQM-P229: Pilot Study to Measure Absolute Line Intensities of Selected 12C16O Transitions

January 24, 2025
Author(s)
Joseph Hodges, Zachary Reed, Katarzyna Bielska, Manfred Birk, Ruimin Guo, Gang Li, Jeong Sik Lim, Daniel Lisak, Georg Wagner
We present primary spectroscopic measurements of line intensities in the 3-0 vibrational band of 12C16O. This international measurement campaign was organized under the auspices of the Consultative Committee for Amount of Substance (CCQM) and involved six

Lattice Light Shift Evaluations In a Dual-Ensemble Yb Optical Lattice Clock

January 22, 2025
Author(s)
Tobias Bothwell, Roger Brown, Benjamin Hunt, Jacob Siegel, Tanner Grogan, Youssef Hassan, Kyle Beloy, Andrew Ludlow, Kurt Gibble, Takumi Kobayashi, Marianna Safronova, Sergey Porsev
In state-of-the-art optical lattice clocks, beyond-electric-dipole polarizability terms lead to a break-down of magic wavelength trapping. In this Letter, we report a novel approach to evaluate lattice light shifts, specifically addressing recent

Towards Precision Spectroscopy of Antiprotonic Atoms for Probing Strong-field QED

January 15, 2025
Author(s)
Goncalo Baptista, Shikha Rathi, Michael Roosa, Quentin Senetaire, Jonas Sommerfeldt, Toshiyuki Azuma, Daniel Becker, Francois Butin, Ofir Eizenberg, Joseph Fowler, Hiroyuki Fujioka, Davide Gamba, Nabil Garroum, Mauro Guerra, Tadashi Hashimoto, Takashi Higuchi, Paul Indelicato, Jorge Machado, Kelsey Morgan, Francois Nez, Jason Nobles, Ben Ohayon, Shinji Okada, Daniel Schmidt, Daniel Swetz, Joel Ullom, Pauline Yzombard, Marco Zito, Nancy Paul
PAX (antiProtonic Atom X-ray spectroscopy) is a new experiment with the aim to test strong-field quantum electrodynamics (QED) effects by performing high-precision x-ray spectroscopy of antiprotonic atoms. By utilizing advanced microcalorimeter detection

DAmodel: Hierarchical Bayesian Modelling of DA White Dwarfs for Spectrophotometric Calibration

December 11, 2024
Author(s)
Benjamin M. Boyd, Gautham Narayan, Kaisey Mandel, Matthew Grayling, Aidan Berres, Mai Li, Aaron Do, ABHIJIT SAHA, Tim Axelrod, Thomas Matheson, Edward W Olszewski, ralph bohlin, Annalisa Calamida, Jenna Claver, Susana Deustua, Jay Holberg, Ivan Hubeny, John MacKenty, Konstantin Malanchev, Sean Points, Armin Rest, Elena Sabbi, Christopher Stubbs
standards (16.5 V 19.5) alongside the three CALSPEC standards, from 900 Å to 32 μm. The framework is the first of its kind to jointly infer photometric zeropoints and WD parameters (log g, Teff, AV , RV ) by simultaneously modelling both photometric and

Activity measurements and calibrations for 225Ac in radioactive equilibrium with its progeny

December 9, 2024
Author(s)
Denis Bergeron, Gulakhshan Hamad, Brittany Broder, Jeffrey Cessna, Adam Pearce, Jerome LaRosa, Leticia Pibida, Brian E. Zimmerman
The massic activity of 225Ac in 0.1 mol/L HCl was measured by multiple primary methods over four consistent measurement campaigns. Results from the triple-to-double coincidence ratio (TDCR) method of liquid scintillation (LS) counting were in accord with

Atomistic Origins of Conductance Switching in an e-Cu0.9V2O5 Neuromorphic Single Crystal Oscillator

December 4, 2024
Author(s)
Cherno Jaye, Conan Weiland, Daniel Fischer, John Ponis, Nicholas Jerla, George Agbeworvi, Saul Perez-Beltran, Nitin Kumar, Kenna Ashen, Jialu Li, Edrick Wang, Michelle A. Smeaton, Fatme Jardali, Sarbajeet Chakraborty, Patrick J. Shamberger, Katherine L. Jungjohann, Lu Ma, Jinghua Guo, G Sambandamurthy, Xiaofeng Qian, Sarbajit Banerjee
: Building artificial neurons and synapses is key to achieving the promise of energy efficiency and acceleration envisioned for brain-inspired information processing. Emulating the spiking behavior of biological neurons in physical materials requires

Heterogeneously integrated AlGaAs/GaAs photodiodes on tantala waveguides

December 1, 2024
Author(s)
Masoud Jafari, Tasneem Fatema, David Carlson, Scott Papp, Andreas Beling
We demonstrate the first heterogeneously integrated high-speed waveguide photodiode (PD) on tantalum pentoxide (Ta2O5, or tantala) for visible light detection. The PDs have 100 pA dark current, more than 56% quantum efficiency (QE) between 635 nm and 780
Displaying 1 - 25 of 2430