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Displaying 2301 - 2325 of 2958

Improved interspecies optical clock comparisons through differential spectroscopy

November 28, 2022
Author(s)
May E. Kim, Will McGrew, Nicholas Nardelli, Ethan Clements, Youssef Hassan, Xiaogang Zhang, Jose Valencia, Holly Leopardi, David Hume, Tara Fortier, Andrew Ludlow, David Leibrandt
Comparisons of high-accuracy optical atomic clocks \citeLudlow2015} are essential for precision tests of fundamental physics \citeSafronova2018}, relativistic geodesy \citeMcGrew2018, Grotti2018, Delva2019}, and the anticipated redefinition of the SI

Liquid-Phase Speed of Sound and Vapor-Phase Density of Difluoromethane

September 23, 2022
Author(s)
Aaron Rowane, Elizabeth Rasmussen, Mark O. McLinden
Difluoromethane (HFC-32, DFM), with a global warming potential (GWP) of 677, is of interest as a pure refrigerant and as a component in low-GWP refrigerant mixtures. Additionally, difluoromethane has recently been identified as a safe, liquefied-gas

Heterosubstrate Illumination Effects in III-V Solar Cells

February 16, 2022
Author(s)
Brianna Conrad, Behrang Hamadani
Reference cell-based current versus voltage ( I–V ) measurements assume that the effect of an illumination spectrum on a solar cell's performance can be fully captured by the multiplication of the spectrum with the device's spectral response and subsequent

Graded Magnetic Materials

May 17, 2021
Author(s)
Lorenzo Fallarino, Brian Kirby, Eric E. Fullerton
Graded magnetic materials represent a promising new avenue in modern material science from both fundamental and application points of view. Over the course of the last few years, remarkable results have been obtained in (epitaxial) heterostructures based

New Practical Multivariate Signatures from a Nonlinear Modifier

April 1, 2021
Author(s)
Daniel Smith-Tone
Multivariate cryptography is dominated by schemes supporting various modifiers to patch certain algebraic weaknesses. Typically these modifiers are linear in nature--- either requiring an extra composition with an affine map, or being evaluated by a

Resolution of the paradox of the diamagnetic force on the Kibble coil

January 13, 2021
Author(s)
Stephan Schlamminger, Shisong Li, Rafael Marangoni, Darine El Haddad, Qing Wang, Wei Zhao
Employing very simple electro-mechanical principles known from classical physics, the Kibble balance establishes a very precise and absolute link between quantum electrical standards and macroscopic mass or force measurements. The success of the Kibble

Phase-coherent sensing of the center-of-mass motion of trapped-ion crystals

November 9, 2020
Author(s)
Matthew Affolter, Kevin Gilmore, Elena Jordan, John Bollinger
Measurements of the center-of-mass motion of a trapped-ion crystal that are phase- coherent with an external force are reported. These experiments are conducted far from the trap motional frequency on a two-dimensional trapped ion crystal of approximately

Plasmon Lasers

August 26, 2020
Author(s)
Wenqi Zhu, Shawn M. Divitt, Matthew S. Davis, Cheng Zhang, Ting Xu, Henri Lezec, Amit Agrawal
… as a promising candidate. In this article, we describe the fundamentals of surface plasmons, and the various embodiments …

Proteomics in non-model organisms: a new analytical frontier

August 9, 2020
Author(s)
Michelle Heck, Ben Neely
For the last century we have relied on model organisms to help understand fundamental biological processes. Now, with advancements in genome sequencing, assembly and annotation, non-model organisms may be studied with the same advanced bioanalytical

Sensitive neutron transverse polarization analysis using a 3He spin filter

July 7, 2020
Author(s)
Y.- Y. Jau, Wangchun Chen, Thomas R. Gentile, Daniel S. Hussey
We report an experimental implementation for neutron transverse polarization analysis that is able to detect a small angular change (10^-3 rad) of neutron spin orientation and works for both monochromatic and polychromatic neutron beams. Our approach

Microwave measurement beyond the quantum limit with a nonreciprocal amplifier

April 2, 2020
Author(s)
Florent Lecocq, Leonardo Ranzani, Gabriel A. Peterson, Katarina Cicak, Anja Metelmann, Shlomi S. Kotler, Raymond Simmonds, John Teufel, Jose Aumentado
The measurement of a quantum system is often performed by encoding its state in a single observable of a light field. The measurement efficiency of this observable can be reduced by loss or excess noise on the way to the detector. Even a quantum-limited

Mid-Infrared Frequency Comb Generation and Spectroscopy with Few-Cycle Pulses and hd2TH Nonlinear Optics

April 1, 2020
Author(s)
Alexander Lind, Abijith S. Kowligy, Henry R. Timmers, Flavio Caldas da Cruz, Nima Nader, Myles C. Silfies, Thomas K. Allison, Scott Papp, Scott Diddams
The mid-infrared atmospheric window of 3–5.5 μm holds valuable information regarding molecular composition and function for fundamental and applied spectroscopy. Using a robust, mode-locked fiberlaser source of 11 fs pulses in the near infrared, we

Observation of an isomerizing double-well quantum system in the condensed phase

January 10, 2020
Author(s)
Varun Verma, Jascha A. Lau, Arnab Choudhury, Li Chen, Dirk Schwarzer, Alec M. Wodtke
Molecules are quantum objects; therefore, isomerization fundamentally involves quantum states bound within a molecular potential energy function with multiple minima. For isolated gas-phase molecules, eigenstates well above the isomerization saddle points

Atomic-scale mechanism of unidirectional oxide growth

November 14, 2019
Author(s)
Xianhu Sun, Wenhui Zhu, Dongxiang WU, Zhenyu Liu, Xiaobo Chen, Lu Yuan, Guofeng Wang, Renu Sharma, Guangwen Zhou
A fundamental knowledge of the unidirectional growth mechanisms is required for precise control on size, shape, and thereby functionalities of nanostructures. Using transmission electron microscopy that spatially and temporally resolves CuO nanowire growth

A Modelling Framework for Householder Decision-Making for Wildfire Emergencies

August 14, 2019
Author(s)
Ruggiero Lovreglio, Erica D. Kuligowski, Steve Gwynne, Ken Strahan
The occurrence of wildfire threats has dramatically increased in the last few decades creating serious challenges for hundreds of thousands of communities around the world. Understanding the physical and social dynamics characterizing wildfires is

PHOTONIC THERMOMETRY: UPENDING 100 YEAR-OLD PARADIGM IN TEMPERATURE METROLOGY

August 1, 2019
Author(s)
Zeeshan Ahmed, Nikolai N. Klimov, Thomas P. Purdy, Tobias K. Herman, Kevin O. Douglass, Ryan P. Fitzgerald
For the past century, industrial temperature measurements have relied on resistance measurement of a thin metal wire or thin metal film whose resistance varies with temperature. Today’s resistance thermometers can routinely measure temperatures with

Ultrafast Optical Pulse Shaping using Dielectric Metasurfaces

May 2, 2019
Author(s)
Shawn M. Divitt, Wenqi Zhu, Cheng Zhang, Henri Lezec, Amit Agrawal
Simultaneous control of individual frequency-comb lines, and their modulation at the repetition-rate of an ultrafast laser represents the ultimate limit of optical pulse shaping. Remarkable progress in mode-locked lasers and chirped pulse amplifiers

Monitoring Fast, Voxel-Scale Cure Kinetics via Sample-Coupled-Resonance Photorheology

February 13, 2019
Author(s)
Callie I. Higgins, Lewis M. Cox, Frank W. DelRio, Jason P. Killgore
Photopolymerizable materials are the focus of extensive research across a variety of fields ranging from additive manufacturing to regenerative medicine. However, poorly understood material mechanical and rheological properties during polymerization at the

Calculation of the impulse response and phase noise of a high-current photodetector using the drift-diffusion equations

February 4, 2019
Author(s)
Franklyn Quinlan, Seyed Ehsan Jamali Mahabadi, Shaokang Wang, Thomas F. Carruthers, Curtis R. Menyuk, Meredith N. Hutchinson, Jason D. McKinney, Keith J. Williams
We describe a procedure to calculate the impulse response and phase noise of high-current photodetectors using the drift-diffusion equations while avoiding computationally expensive Monte Carlo simulations. We apply this procedure to a modified uni
Displaying 2301 - 2325 of 2958
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