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.
Parametrized tight-binding models fit to first principles calculations can provide an efficient and accurate quantum mechanical method for predicting properties of molecules and solids. However, well-tested parameter sets are generally only available for a
Stephen Moxim, James P Ashton, Mark Anders, Jason Ryan
This work explores the atomic-scale nature of defects within hafnium dioxide/silicon dioxide/silicon (HfO2/SiO2/Si) transistors generated by hot-carrier stressing. The defects are studied via electrically detected magnetic resonance (EDMR) through both
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
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.
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
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
Megan Kelleher, Charles McLemore, Dahyeon Lee, Josue Davila-Rodriguez, Scott Diddams, Franklyn Quinlan
We develop and demonstrate a compact (less than 6 mL) portable Fabry-Pérot optical reference cavity. A laser locked to the cavity is thermal noise limited at 2 × 10−14 fractional frequency stability. Broadband feedback control with an electro-optic
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
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