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Michael S. Foss-Feig, Kaden R. Hazzard, John J. Bollinger, Ana Maria Rey, Charles W. Clark
Ising models, and the physical systems described by them, play a central role in generating entangled states for use in quantum metrology and quantum information. In particular, ultracold atomic gases, trapped ion systems, and Rydberg atoms realize long
We calculate electron energy loss spectra (EELS) for composite plasmonic structures based on silicene and germanene. A continued-fraction expression for the effective dielectric function is used to perform multiscale calculations of EELS for both silicene
John M. Moreland, Yoshihiro Nakashima, Jacob W. Alldredge, Gary Zabow
New instrumentation is being developed to better understand the in vivo properties of magnetic particles suspended in solution or lodged in tissue. We describe three novel methods with the necessary sensitivity to measure the microscopic magnetic
Elizabeth A. Donley, Francois-Xavier R. Esnault, Eric M. Blanshan, Eugene N. Ivanov, Robert E. Scholten, John E. Kitching
Miniature atomic clocks based on coherent population trapping (CPT) states in thermal atoms are emerging as an important component in many field applications, particularly where satellite frequency standards are not accessible. Cold-atom CPT clocks promise
William H. Rippard, Matthew R. Pufall, Anthony B. Kos
We have injection-locked a spin-transfer oscillator to a second-harmonic electrical input signal and measured the relative phase and amplitude of the device output as a function of DC current under steady-state conditions. The relative phase of the device
Mohammad Hafezi, Jingyun Fan, Alan L. Migdall, Jacob M. Taylor
Systems with topological oder exhibit exotic phenomena including fractional statistics. While most systems with topological order have been electronic, advances in our understanding of synthetic gauge fields have enabled realization of topological order in
We study downsampling of optical frequency combs by way of pulse gating to enable efficient spectral broadening and f-2f interferometry. We downsample a 250 MHz repetition-rate comb to 25 MHz, thereby enabling detection of the comb's carrier-envelope
P. Jonsson, P. Bengtsson, J. Ekman, S. Gustafsson, L. B. Karlsson, G. Gaigalas, D. Kato, Charlotte F. Fischer, I. Murakami, H. A. Sakaue, H. Hara, T. Watanabe, N. Nakamura, N. Yamamoto
Energies, E1, M1, E2, M2 transition rates, oscillator strengths, and lifetimes from relativistic configuration interaction calculations are reported for the states of the 2p6, 2p53s, 2p53p, and 2p53d, configurations in all Ne-like ions between Mg III and
Charlotte F. Fischer, S. Verdebout, Michel Godefroid, P. Rynkun, P. Jonsson, G. Gaigalas
No lines have been observed for transitions between the doublet and quartet levels of B i. Consequently,energy levels based on observation for the latter are obtained through extrapolation of wavelengths along the iso-electronic sequence for the 2s22p 2Po
Johannes Hubmayr, Hsiao-Mei Cho, Gene C. Hilton, Kent D. Irwin, Duncan Hanson
Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "Β-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant
Michael A. Lombardi, J. Mauricio Lopez-Romero, Nelida Diaz-Munoz
This paper describes a frequency and time control system developed by the Sistema Interamericano de Metrologia (SIM). Due to limited resources, some SIM national metrology institutes maintain a low-cost rubidium clock as their national time standard
P. Rynkun, P. Jonsson, G. Gaigalas, Charlotte F. Fischer
Based on relativistic wave functions from multiconfiguration Dirac-Hartree-Fock and configuration interaction calculations, E1, M1, E2, M2 transition rates, weighted oscillator strengths, and lifetimes are evaluated for the states of the (1s2)2s22p4; 2s2p5
Deirdre Kilbane, John D. Gillaspy, Yuri Ralchenko, Joseph Reader, G. O'Sullivan
Measurements of extreme ultraviolet radiation from gadolinium, dysprosium and tungsten ions with an open n=4 shell were performed at the National Institute of Standards and Technology. The ions were produced and confined in an electron beam ion trap and
Nadir S. Faradzhev, Monica McEntee, John Yate, Shannon B. Hill, Thomas B. Lucatorto
We report the photo-deposition of a carbonaceous layer grown on a TiO2 thin film by EUV radiation-induced chemistry of adsorbed n-tetradecane and the subsequent photo-oxidation of this film. It is found by chemical analysis of the C layer that irradiation
Yuri Ralchenko, John D. Gillaspy, Joseph Reader, Dmitry D. Osin, John J. Curry, Yuri A. Podpaly
We present a review of measurements and analyses of extreme-ultraviolet magneticdipole (M1) lines in 50-60-times ionized atoms of tungsten, hafnium, tantalum, and gold with an open 3d shell. The spectra were measured with the electron beam ion trap at the
George P. Eppeldauer, Howard W. Yoon, Dean G. Jarrett, Thomas C. Larason
For photocurrent measurements with low uncertainties, wide-dynamic range reference current-to-voltage converters and a new converter calibration method have been developed at the National Institute of Standards and Technology (NIST). The high feedback
Marc A. Weiss, J C. Eidson, Charles Barry, L Goldin, Bob Iannucci, Edward Lee, Kevin Stanton
A new economy built on the massive growth of endpoints on the internet will require precise and verifiable timing in ways that current systems do not support. Applications, computers and communications systems have been developed with modules and layers
Scott A. Diddams, Hansuek Lee, Myoung-Gyun Suh, Tong Chen, Jiang Li, Kerry J. Vahala
Frequency references are indispensable to radio, microwave, and time keeping systems, with far reaching applications in navigation, communi- cation, remote sensing, and basic science. Over the past decade there has been an optical revo- lution in time
Marc A. Weiss, Calvin Miles, Karl J. Kovach, John Dobyne, Karen Van Dyke
The Global Positioning System (GPS) integrity architecture forms the basis for several GPS integrity augmentation systems, most notably, the Wide Area Augmentation System (WAAS), Receiver-based Autonomous Integrity Monitoring (RAIM) and its proposed
John J. Bollinger, Joseph W. Britton, Brian C. Sawyer
By employing forces that depend on the internal electronic state (or spin) of an atomic ion, the Coulomb potential energy of a trapped ion crystal can be modified in a spin-dependent way to mimic effective quantum spin Hamiltonians. We use simple models to
Andrew D. Ludlow, Nathan M. Hinkley, Jeffrey A. Sherman, Nate B. Phillips, Marco Schioppo, Nathan D. Lemke, Kyle P. Beloy, M Pizzocaro, Christopher W. Oates
Atomic clocks have been transformational in science and technology, leading to innovations such as global positioning, advanced communications, and tests of fundamental constant variation. Next-generation optical atomic clocks can extend the capability of
The daily variation (diurnal) in the two-way satellite time and frequency transfer (TWSTFT) difference is one of the most significant instabilities of the TWSTFT technique. The diurnal comes from the daily delay change of the TWSTFT signal paths. In recent
Justin Shaw, Thomas J. Silva, Hans Nembach, Emrah Turgut, Patrik Grychtol, Chan La-O-Vorakiat, Henry C. Kapteyn, Margaret M. Murnane, Stefan Mathias, Martin Aeschlimann, Claus Schneider, Daniel E. Adams
In the following, we show that the conclusions of our article titled "Ultrafast Demagnetization Measurements Using Extreme Ultraviolet Light: Comparison of Electronic and Magnetic Contributions" are correct. The Comment of Vodungbo et al. argues that a
Archita Hati, Craig W. Nelson, Corey A. Barnes, Danielle G. Lirette, Tara M. Fortier, Franklyn J. Quinlan, Jason A. DeSalvo, Andrew D. Ludlow, Till P. Rosenband, Scott A. Diddams, David A. Howe
We present the design of a novel, ultra-low phase-noise frequency synthesizer implemented with extremely low noise regenerative frequency dividers. This synthesizer generates eight outputs viz. 1.6 GHz, 320 MHz, 160 MHz, 80 MHz, 40 MHz, 20 MHz, 10 MHz and