An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Ian B. Spielman, Dina Genkina, Alina M. Pineiro Escalera, Hsin-I Lu, Lauren Aycock
Physical systems with non-trivial topological order find direct applications in metrology[1] and promise future applications in quantum computing[2,3]. The quantum Hall effect derives from transverse conductance, quantized to unprecedented precision in
Jack F. Douglas, Hao Zhang, Xinyi Wang, Alexandros Chremos
Crystalline materials at elevated temperatures and pressures can exhibit properties more reminiscent of simple liquids than ideal crystalline materials, an attribute making these materials useful in diverse applications. Superionic crystalline materials
Nathan Mahynski, Evan Pretti, Vincent K. Shen, Jeetain Mittal
We demonstrate a method based on symmetry to predict the structure of multi-component colloidal mixtures. In this work we focus on two-dimensional systems, for which the method allows us to exhaustively enumerate candidates from all wallpaper groups
Raghavendra Srinivas, Shaun C. Burd, R. T. Sutherland, Andrew C. Wilson, David J. Wineland, Dietrich G. Leibfried, David T. Allcock, Daniel H. Slichter
We present a new method of spin-motion coupling for trapped ions using microwaves and a magnetic field gradient oscillating close to the ions' motional frequency. We demonstrate and characterize this coupling experimentally using a single ion in a surface
Joshua A. Gordon, Christopher L. Holloway, Matthew T. Simons, Abdulaziz H. Haddab
Rydberg atoms have been used for measuring radio-frequency (RF) electric (E)-fields due to their strong dipole moments over the frequency range of 500 MHz-1 THz. For this, electromagnetically induced transparency (EIT) within the Autler-Townes (AT) regime
The three-spin-1/2 decoherence-free subsystem defines a logical qubit protected from collective noise and supports exchange-only universal gates. Such logical qubits are well-suited for implementation with electrically-defined quantum dots. Exact exchange
We study the stochastic dynamics of a particle subject to a periodically driven potential. For atomic ions trapped in radio-frequency Paul traps, noise heating and laser cooling typically act slowly in comparison with the timescale of the unperturbed
Jack F. Douglas, Wenjie Xia, Nitin K. Hansoge, Wen-Sheng Xu, Sinan Keten, Frederick R. Phelan Jr.
We apply the recently developed energy renormalization (ER) method to coarse-graining representative polymer melts having a relatively low, intermediate and high degree of glass fragility, i.e., polybutadiene, polystyrene, and polycarbonate, respectively
Moshe Shuker, Juniper Wren Y. Pollock, Rodolphe Boudot, V. I. Yudin, A. V. Taichenachev, John E. Kitching, Elizabeth A. Donley
Light-induced frequency shifts can be a key limiting contribution to the mid and long-term frequency stability in atomic clocks. In this letter, we demonstrate the experimental implementation of the combined error signal (CES) interrogation protocol to a
William F. McGrew, Xiaogang Zhang, Robert J. Fasano, Holly Leopardi, Daniele Nicolodi, Kyle P. Beloy, Jian Yao, Jeffrey A. Sherman, Stefan A. Schaeffer, Joshua J. Savory, Stefania Romisch, Christopher W. Oates, Thomas E. Parker, Tara M. Fortier, Andrew D. Ludlow
The pursuit of ever more precise measures of time and frequency motivates redefinition of the second in terms of an optical atomic transition. To ensure continuity with the current definition, based on the microwave hyperfine transition in 133Cs, it is
We carried out molecular dynamics simulations on thin free-standing films of Lennard-Jones fluid with a view of establishing the range in which the films are thermodynamically stable. thermophysical and interfacial properties were studied as a function of
R. J. Lewis-Swan, Arghavan Safavi-Naini, John Bollinger, Ana Maria Rey
Scrambling of quantum information is the process by which information initially stored in the local degrees of freedom of a quantum many-body system spreads over its many-body degrees of freedom, becoming inaccessible to local probes and thus apparently
Hans Pieter Mumm, Denis E. Bergeron, Mark Tyra, Jerome LaRosa, Svetlana Nour
The Precision Reactor Oscillation and Spectrum Experiment, PROSPECT, is designed to make both a precise measurement of the antineutrino spectrum from a highly-enriched uranium reactor and to probe eV-scale sterile neutrinos by searching for neutrino
Scott W. Schmucker, Pradeep Namboodiri, Ranjit Kashid, Xiqiao Wang, Binhui Hu, Jonathan Wyrick, Alline Myers, Joshua D. Schumacher, Richard M. Silver, Michael Stewart
Scanning tunneling microscopy (STM) enables the fabrication of 2-D delta-doped structures in Si with atomistic precision, with applications from tunnel field effect transistors to qubits. The combination of a very small contact area and the restrictive
R. T. Sutherland, Raghavendra Srinivas, Shaun C. Burd, Dietrich Leibfried, Andrew C. Wilson, David J. Wineland, David T. Allcock, Daniel Slichter, S. B. Libby
We present a general theory for laser-free entangling gates with trapped-ion hyperfine qubits, using either static or oscillating magnetic-field gradients combined with a pair of uniform microwave fields symmetrically detuned about the qubit frequency. By
James E. Lawler, FNU Hala, Chris Sneden, Gillian Nave, M. P. Wood, John J. Cowan
New branching fraction (BF) measurements from 24 Fourier transform spectra calibrated using standard lamps and the Ar branching ratio (BR) method are reported. The BFs for 259 lines are converted to absolute atomic transition probabilities using published
Hans Pieter Mumm, Denis E. Bergeron, Mark Tyra, Svetlana Nour, Jerome LaRosa
This work reports the production and characterization of lithium-loaded liquid scintillators (LiLS) for the Precision Reactor Oscillation and Spectrum Experiment (PROSPECT). Fifty-nine 90 L batches of LiLS (6Li mass fraction 0.082%0.001%) were produced
Christine G. Pappas, Malcolm S. Durkin, Joseph W. Fowler, Kelsey M. Morgan, Joel N. Ullom, William B. Doriese, Gene C. Hilton, Galen C. O'Neil, Daniel R. Schmidt, Paul Szypryt, Daniel S. Swetz
The Non-destructive Statistical Estimation of Nanoscale Structures and Electronics NSENSE instrument for IARPAs Rapid Analysis of Various Emerging Nanoelectronics RAVEN program is a tabletop X-ray tomography prototype designed for three-dimensional imaging
There have been significant recent advances in realizing bandstructures with geometrical and topological features in experiments on cold atomic gases. We provide an overview of these developments, beginning with a summary of the key concepts of geometry
Moshe Shuker, Juniper Wren Y. Pollock, Rodolphe Boudot, V. I. Yudin, A. V. Taichenachev, John E. Kitching, Elizabeth A. Donley
Sophisticated Ramsey-based interrogation protocols using composite laser pulse sequences have been recently proposed to provide in next-generation high-precision atomic clocks a near perfect elimination of frequency shifts induced during the atom-probing
We experimentally investigate the effect of parametric instabilities on the short-time heating process of periodically- driven bosons in 2D optical lattices with a continuous transverse (tube) degree of freedom. We analyze three types of periodic drives (i
This article describes electron energy-loss spectroscopy (EELS), energy-filtering transmission electron microscopy (EFTEM) and electron spectroscopic diffraction (ESD) in a transmission electron microscope (TEM) or in a scanning transmission electron
Matti Silveri, S Masuda, Vasilii Sevriuk, K-Y Tan, Mate Jenei, Eric Hyyppa, Fabian Hassler, Matti Partanen, Jan Goetz, Russell Lake, Leif Gronberg, Mikko Mottonen
The shift of the energy levels of a quantum system owing to broadband electromagnetic vacuum fluctuations-the Lamb shift-has been central for the development of quantum electrodynamics and for the understanding of atomic spectra. Identifying the origin of