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Charlotte F. Fischer, Michel Godefroid, T Brage, P. Jonsson, G. Gaigalas
Multiconfiguration wave function expanssions combined with configuration interaction methods are a method of choice for complex atoms where atomic state functions are expanded in a basis of configuration state functions. Combined with a variational method
Recently, as part of a study of the ability of a Gaussian standing-wave interference field to sort small dielectric spheres entrained in a moving fluid, we implemented a two-length-scale method to determine the trajectories of the particles. In the first
Franklyn J. Quinlan, Tara M. Fortier, A. Rolland, Frederick N. Baynes, A. J. Metcalf, Archita Hati, Andrew D. Ludlow, Nathan M. Hinkley, M. Shimizu, Joe Campbell, Scott A. Diddams
Increasing demands in the high tech industry for higher data rates and better synchronization necessitates the development of new wideband and tunable sources with improved noise performance over traditional synthesis based quartz oscillators. Precision
There is a need to back up critical timing infrastructure at the national level. This paper provides an update on a joint project employing commercial equipment to send national timing signals through a telecommunication network. This experiment connects
T D. Shoji, W Xie, Kevin L. Silverman, Ari Feldman, Todd E. Harvey, Richard Mirin, Thomas Schibli
Low-noise, high-repetition-rate mode-locked solid-state lasers are attractive for precision measurement and microwave generation, but the best lasers in terms of noise performance still consist of complex, bulky optical setups, which limits their range of
Gregory W. Hoth, Bruno M. Pelle, Stefan Riedl, John E. Kitching, Elizabeth A. Donley
We demonstrate a two axis gyroscope by use of light pulse atom interferometry with an expanding cloud of atoms in the regime where the cloud has expanded by 1.1 to 5 times its initial size during the interrogation. Rotations are measured by analyzing
Ryan C. Terrien, Samuel Halverson, Suvrath Mahadevan, Arpita Roy, Chad Bender, Guomundur K. Stefansson, Andrew Monson, Eric Levi, Fred Hearty, Cullen Blake, Michael McElwain, Christian Schwab, Lawrence Ramsey, Jason Wright, Sharon Wang, Qian Gong, Paul Robertson
We describe a detailed radial velocity error budget for the NASA-NSF Extreme Precision Doppler Spectrometer instrument concept NEID (NN-explore Exoplanet Investigations with Doppler spectroscopy). Such an instrument performance budget is a necessity for
To do a better time comparison between high-precision clocks (such as Cesium Fountain clock and Hydrogen-maser clock), we want to study and eventually lower the GPS carrier-phase time transfer noise. The GPS carrier-phase time transfer noise comes from
Magnetic Random Access Memory (MRAM) possesses a unique combination of attributes that provide considerable benefits over those available with conventional memory technology. Here we discuss the state-of-the-art of MRAM, from parts currently in production
Ryan C. Terrien, Andrew J. Monson, Chad Bender, Samuel P. Halverson, Larry Ramsey
Infrared detectors with cutoff wavelengths of ∼ 1.7 μm have much lower sensitivity to thermal background contamination than those with longer cutoff wavelengths. This low sensitivity offers the attractive possibility of reducing the need for fully
John P. Gaebler, Ting R. Tan, Yong Wan, Yiheng Lin, Ryan S. Bowler, Adam C. Keith, Scott Glancy, Kevin Coakley, Emanuel Knill, Dietrich Leibfried, David J. Wineland
We report high-fidelity laser-beam-induced quantum logic gates on qubits comprised of hyperfine states in 9Be+ ions, achieved in part through a combination of improved laser beam quality and control and improved state preparation. We demonstrate single
Hojoong Jung, Xiang Guo, Na Zha, Scott Papp, Scott Diddams, Hong X. Tang
Nonlinear optical conversion with frequency combs is important for self-referencing and for generating shorter wavelength combs. Here we demonstrate high-efficiency frequency-comb doubling through the combination of second-harmonic generation (SHG) and sum
Haje Korth, Kim Strohbehn, Francisco Tejada, Andreas G Andreou, John Kitching, Svenja A. Knappe, S. John Lehtonen, Shaughn M. London, Matiwos Kafel
A miniature absolute scalar magnetometer based on the rubidium isotope 87Rb was developed for possible future operation in space. The instrument design implements both Mx and Mz mode operation and leverages a novel micro-electro-mechanical systems (MEMS)
Daniel C. Cole, Erin S. Lamb, Pascal P. Del'Haye, Scott A. Diddams, Scott B. Papp
Solitons are pulses which propagate without spreading due to a balance between nonlinearity and dispersion or diffraction, and are universal features of systems exhibiting these effects. They are important in plasma physics, fluid dynamics, atomic physics
This work treats diffraction corrections in radiometry for cases of point and extended sources in symmetric three-element systems. It considers diffraction effects for both spectral power and total power in cases of Planckian sources. This improves upon an
Simple kinematic considerations indicate that, under certain conditions in radio-frequency (rf) plasmas, the amplitude of the low-energy peak in ion energy distributions (IEDs) measured at an electrode depends sensitively on ion velocities upstream, at the
Johannes Hubmayr, Jason E. Austermann, James A. Beall, Daniel T. Becker, Shannon M. Duff, Arpi L. Grigorian, Gene C. Hilton, Joel N. Ullom, Michael R. Vissers
We describe 280 GHz bolometric detector arrays that instrument the balloon-borne polarimeter spider. A primary science goal of spider is to measure large-scale B-mode polarization of the cosmic microwave back-ground (cmb) in search of the cosmic-inflation
Evgheni Strelcov, Anton Ievlev, Alex Belianinov, Alexander Tselev, Andrei A. Kolmakov, Sergei Kalinin
We report a synergistic approach of micro-Raman spectroscopic mapping and deep data analysis to study the distribution of crystallographic phases and ferroelastic domains in a defected Al-doped VO2 microcrystal. Bayesian linear unmixing revealed an uneven
Zhensheng Tao, Cong Chen, Tibor Szilvasi, Mark W. Keller, Manos Mavrikakis, Henry C. Kapteyn, Margaret M. Murnane
Attosecond spectroscopic techniques have made it possible to measure differences in transport times for photoelectrons from localized core levels and delocalized valence bands in solids. We report the application of attosecond pulse trains to directly and
Kevin J. Coakley, Benjamin Miller, Stephen A. Montzka, Colm Sweeney, Ben Miller, John B. Miller
In contrast to CO2 produced in the atmosphere by all other sources, CO2 produced by the combustion of fossil fuels is devoid of 14C. Thus, the measured 14C: 12C isotopic ratio of atmospheric CO2 (and its associated derived {Δ}14C value) is an ideal tracer
Joseph W. Britton, John J. Bollinger, Justin G. Bohnet, Brian C. Sawyer, Hermann Uys, Michael Biercuk
Superconducting magnets enable precise control of nuclear and electron spins, and are used in experiments that explore biological and condensed matter systems, and fundamental atomic particles. In high-precision applications, a common view is that that
William Loh, Matthew T. Hummon, Holly Leopardi, Tara Fortier, Franklyn Quinlan, John Kitching, Scott Papp, Scott Diddams
We frequency stabilize the output of a miniature stimulated Brillouin scattering (SBS) laser to rubidium atoms in a microfabricated cell to realize a laser system with frequency stability at the 10-11 level over seven decades in averaging time. In addition
Cell membranes, composed primarily of lipid bilayers, are dynamically active structures. While the relationship between heterogeneity of dynamics and biological function is becoming increasingly appreciated, the dynamical characteristics of lipid membranes