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Displaying 101 - 125 of 2238

Quantum back-action limits in dispersively measured Bose-Einstein condensates

April 8, 2023
Author(s)
Ian Spielman, Emine Altuntas
A fundamental tenet of quantum mechanics is that measurements change a system's wavefunction to that most consistent with the measurement outcome, even if no observer is present. Weak measurements produce only limited information about the system, and as a

NIST Time and Frequency Bulletin

April 4, 2023
Author(s)
Kelsey Rodriguez
The Time and Frequency Bulletin provides information on performance of time scales and a variety of broadcasts (and related information) to users of the NIST services.

Toward improved quantum simulations and sensing with trapped two-dimensional ion crystals via parametric amplification

March 29, 2023
Author(s)
Matthew Affolter, Wenchao Ge, Bryce Bullock, Shaun Burd, Kevin Gilmore, Jennifer Lilieholm, Allison Carter, John J. Bollinger
Improving coherence is a fundamental challenge in quantum simulation and sensing experiments with trapped ions. Here we discuss, experimentally demonstrate, and estimate the potential impacts of two different protocols that enhance, through motional

Interference induced anisotropy in a two-dimensional dark state optical lattice

March 27, 2023
Author(s)
Ian Spielman, Gediminas Juzeliunas, Edvinas Gvozdiovas
We describe a two-dimensional optical lattice for ultracold atoms with spatial structure below the diffraction limit created by a bichromatic optical standing wave. At every point in space these fields couple the internal atomic states in a three-level

Controlling solute trapping and solute drag in a phase-field model

March 16, 2023
Author(s)
Arnab Mukherjee, James A. Warren
The finite solid-liquid interface width in phase-field models results in non-equilibrium effects, including solute trapping. Prior phase field modeling has shown that this extra degree of freedom, when compared to sharp-interface models, results in solute

Modeling the linear and nonlinear dielectric response of solvents

March 13, 2023
Author(s)
Michael Woodcox, Avik Mahata, Aaron Hagerstrom, Angela Stelson, Chris Muzny, Ravishankar Sundararaman, Kathleen Schwarz
We demonstrate a method to compute the dielectric spectra of fluids in molecular dynamics by directly applying electric fields to the simulation. We obtain spectra from molecular dynamics simulations with low magnitude electric fields (0.01 V/A) in

VECSEL systems for quantum information processing with trapped beryllium ions

March 10, 2023
Author(s)
Shaun C. Burd, Jussi-Pekka Penttinen, Panyu Hou, Hannah Knaack, Sanna Ranta, Mika Maki, Emmi Kantola, Mircea Guina, Daniel Slichter, Dietrich Leibfried, Andrew C. Wilson
We demonstrate two systems based on vertical-external-cavity surface-emitting lasers (VECSELs) for producing ultraviolet laser light at wavelengths of 235 and 313 nm. The systems are suitable for quantum information processing with trapped beryllium ions

Trap-induced ac Zeeman shift of the thorium-229 nuclear clock frequency

March 8, 2023
Author(s)
Kyle Beloy
We examine the effect of a parasitic rf magnetic field, attributed to ion trapping, on the highly anticipated nuclear clock based on $^229}$Th$^3+}$ [C. J. Campbell \it et al.}, Phys.\ Rev.\ Lett.\ 108, 120802 (2012)]. The rf magnetic field induces an ac

The hazard of UV-induced oxidation to solar-viewing spacecraft optics

March 2, 2023
Author(s)
Charles S. Tarrio, Robert F. Berg, Thomas B. Lucatorto, Dale E. Newbury, Nicholas Ritchie, Andrew Jones, Frank Eparvier
The two most prevalent outgas contaminants on satellites are organic molecules and water vapor. Adsorbed organic molecules can degrade a solar-viewing instrument when they are cracked by ultraviolet radiation (UV) and become a light-absorbing layer of

Versatile quantum-enabled telecom receiver

March 2, 2023
Author(s)
FNU Nur Fajar Rizqi Annafianto, Jabir Marakkarakath Vadakkepurayil, Ivan Burenkov, Abdella Battou, Sergey Polyakov
We experimentally demonstrate a quantum-measurement-based receiver for a range of modulation schemes and alphabet lengths in a telecom C-band. We attain symbol error rates below the shot noise limit for all the studied modulation schemes and the alphabet

AtomVision: A machine vision library for atomistic images

March 1, 2023
Author(s)
Brian DeCost, Ramya Gurunathan, Adam Biacchi, Kamal Choudhary
Computer vision techniques have immense potential for materials design applications. In this work, we introduce an integrated and general-purpose AtomVision library that can be used to generate and curate microscopy image (such as scanning tunneling

Measuring the Frequency Accuracy and Stability of WWV and WWVH

March 1, 2023
Author(s)
Michael A. Lombardi
Radio station WWV, famous for the "at the tone ...." announcements broadcast at the top of each minute, is known to shortwave listeners and radio amateurs worldwide as a trusted source of accurate time. However, you might not know that the original purpose

Thermal and Electronic Properties of Ba2MnSe3

February 15, 2023
Author(s)
Adam Biacchi, Oluwagbemiga Ojo, Wilarachchige Gunatilleke, George Nolas
The structural, thermal, and electronic properties of Ba2MnSe3 were investigated. Analysis of the low-temperature heat capacity revealed a low Debye temperature and a low average speed of sound that, together with the bonding in this material, result in a

Topological charge pumping with subwavelength Raman lattices

February 15, 2023
Author(s)
Ian Spielman, Gediminas Juzeliunas, Domantas Burba, mantas Raciunas
Recent experiments demonstrated deeply subwavelength lattices using atoms with $N$ internal states Raman-coupled with lasers of wavelength $\lambda$. The resulting unit cell was $\lambda/2N$ in extent, an $N$-fold reduction compared to the usual $\lambda/2

Optical and microwave metrology at the 10-18 level with an Er/Yb:glass frequency comb

February 5, 2023
Author(s)
Nicholas Nardelli, Holly Leopardi, THOMAS SCHIBLI, Tara Fortier
Optical frequency combs are an essential tool for precision metrology experiments ranging in application from remote spectroscopic sensing of trace gases to the characterization and comparison of optical atomic clocks for precision time-keeping and
Displaying 101 - 125 of 2238