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Displaying 551 - 575 of 2538

Phase-coherent detection of an optical dipole force by Doppler velocimetry

May 10, 2011
Author(s)
Michael J. Biercuk, Hermann Uys, Joseph W. Britton, Aaron Vandevender, John J. Bollinger
… Doppler detection of optical dipole forces using large ion crystals in a Penning trap. The technique is based on … in 9Be+ near 313 nm and the center-of-mass (COM) ion motional mode. The optical dipole force is tuned to … detailed characterization of motional modes in complex ion crystals and provides frequency discrimination below the …

Classical Trajectories and RRKM Modeling of Collisional Excitation and Dissociation of Benzylammonium and tert Butyl Benzylammonium Ions in a Quadrupole-Hexapole-Quadrupole Tandem Mass Spectrometer

March 1, 2010
Author(s)
Vadim D. Knyazev, Stephen Stein
… of the benzylammonium and the 4-tert butyl benzylammonium ions was studied experimentally in an electrospray ionization … were determined as functions of the kinetic energy of ions and the collider gas (argon) pressure. A theoretical … of the trajectories of the parent and the product ions flight through the hexapole collision cell, …

Scalable arrays of doped silicon RF Paul traps

October 26, 2009
Author(s)
Joseph W. Britton, Dietrich G. Leibfried, James A. Beall, Brad R. Blakestad, Janus H. Wesenberg, David J. Wineland
… and a multi-zone surface-electrode trap. From the measured ion motional heating rate we determine an electric field spectral density at the ion of approximately 1 × 10 -10 (V /m) 2 Hz −1 at ωz /2π {math equals} 1.125 MHz when the ion lies 40 υm above the electrode surface. One application …

3D Molecular Imaging SIMS

July 1, 2006
Author(s)
John G. Gillen, Albert J. Fahey, M Wagner, Christine M. Mahoney
… analyzed by dynamic SIMS using SF 5 + polyatomic primary ion bombardment. Each of these systems exhibited minimal … through the depth of the film. By combing secondary ion imaging with depth profiling, 3-dimensional molecular … sections are cut in the samples with the SF5+ primary ion beam to produce a laterally magnified cross section of …

Computational study of the dielectric properties of [La,Sc] 2 O 3 solid solutions

July 11, 2010
Author(s)
Hiroyoshi Momida, Eric J. Cockayne, Naoto Umezawa, Takahisa Ohno
… predicted at small Sc concentrations due to the rattling ion effect. Similar calculations for a model amorphous La2O3 … the Sc changes in a way that compensates for the rattling ion effect. … gate dielectrics, high-k dielectrics, rattling ion effect …

Collisional Electron-Detachment and Ion Conversion Processes in SF6

November 1, 1990
Author(s)
James K. Olthoff, Richard J. Van Brunt, Yicheng Wang, L. D. Doverspike, R. Champion
… 6th Intl. Swarm Seminar entitled Nonequilibrium Effects in Ion and Electron Transport, … Collisional Electron-Detachment and Ion Conversion Processes in SF6 …

Amorphous Calcium Phosphate/Urethane Methacrylate Resin Composites. I. Physicochemical Characterization

May 7, 2007
Author(s)
William Regnault, Tonya Icenogle, Joseph M. Antonucci, Drago Skrtic
… were polymerized and evaluated for mechanical strength and ion release profiles in different aqueous media. Strength of … and the pH of the liquid environment strongly affected the ion release kinetics. In saline, the UDMA/PEG-U composite … a sustained release for at least 350 h. The initially high ion release of the PEG-U composites decreased after 72 h, …

Fabrication of Lithium Indolide and Derivates for Ion Conduction

September 14, 2022
Author(s)
Jintao Wang, Yang Yu, Anan Wu, Khai Chen Tan, Hui Wu, Teng He, Ping Chen
… Alkali-ion batteries have been widely used nowadays. The development … derivates show pronounced ionic conductivities, e.g., the ion conductivity of sodium carbazolide ditetrahydrofuran … Fabrication of Lithium Indolide and Derivates for Ion Conduction …

A single-atom optical clock with high accuracy

July 14, 2006
Author(s)
Windell Oskay, Scott A. Diddams, Elizabeth A. Donley, Tara M. Fortier, Thomas P. Heavner, Leo W. Hollberg, Wayne M. Itano, Steven R. Jefferts, M J. Jensen, Kyoungsik Kim, F Levi, Thomas E. Parker, James C. Bergquist
… transition in a single, laser-cooled, trapped mercury ion. In this comparison, the fractional systematic frequency … conclusively that frequency control in the mercury-ion system is possible at a level superior to that of the … cesium fountain, femtosecond laser frequency comb, mercury-ion frequency standard, optical frequency standard, …

Quantum Computation, Spectroscopy of Trapped Ions, and Schrodinger Cat

January 1, 1999
Author(s)
David J. Wineland, C Monroe, Wayne M. Itano, D Kielpinski, B E. King, C J. Myatt
… at NIST to implement quantum computation using trapped ions, based on a scheme proposed by J.I. Cirac and P. Zoller … Quantum Computation, Spectroscopy of Trapped Ions, and Schrodinger Cat …

Molecular Mass Determination of Saturated Hydrocarbons: Reactivity of eta- 5 -Cyclopentadienylcobalt Ion (CpCo. +) and Linear Alkanes up to C-30

January 1, 2003
Author(s)
H M. Byrd, Kathleen M. Flynn, D P. Ridge
… the feasibility of the h 5 -cyclopentadienylcobalt ion (CpCo +) as a suitable cationization reagent for saturated hydrocarbons analysis by mass spectrometry. Ion/molecule reactions of CpCo + and three medium … n-alkanes were examined using Fourier-transform ion cyclotron resonance mass spectrometry. Second-order rate …

Frequency Measurements of Al+ and Hg+ Optical Standards

June 8, 2009
Author(s)
Wayne M. Itano, James C. Bergquist, Till P. Rosenband, David J. Wineland, David Hume, Chin-wen Chou, Steven R. Jefferts, Thomas P. Heavner, Tom Parker, Scott Diddams, Tara Fortier
… aluminum ion, mercury ion, optical frequency standards, time variation of fundamental constants, trapped ion frequency standards …

Temperature-Controlled Depth Profiling in Polymeric Biomaterials Using Cluster Secondary Ion Mass Spectrometry

July 1, 2006
Author(s)
Christine M. Mahoney, Albert J. Fahey, John G. Gillen, Chang Xu, J Batteas
… Secondary Ion Mass Spectrometry (SIMS) employing an SF5+ polyatomic primary ion source was used to depth profile through various … rates, damage cross sections, and overall secondary ion stability) were monitored as a function of temperature. … in Polymeric Biomaterials Using Cluster Secondary Ion Mass Spectrometry …

Ab Initio Study of the Reactions Between a Series of Substituted Singlet Nitrenium Ions and Water

October 12, 2021
Author(s)
A A. Restrepo-Cossio, M Marquez, F Mari, Carlos A. Gonzalez
… the reactions of a series of substituted singlet nitrenium ions ( 1 [R-N-H] + , R=H, Cl, F, CN and Me) and water in gas … It was found that in gas phase and solution the nitrenium ions react in a barrierless fashion to produce an ylide-like … Between a Series of Substituted Singlet Nitrenium Ions and Water …

An 27 Al+ quantum-logic clock with systematic uncertainty below 10 -18

July 15, 2019
Author(s)
Samuel M. Brewer, Jwo-Sy Chen, Aaron M. Hankin, Ethan Clements, Chin-wen Chou, David J. Wineland, David Hume, David Leibrandt
… a frequency stability of 1.2 X 10 -15 /(T 1/2 ). A 25 Mg + ion is simultaneously trapped with the 27 Al + ion and used for sympathetic cooling and state readout during … to previous 27Al+ clocks, enabling clock operation with ion motion near the three-dimensional ground state. Operating …

Quantum interface between an electrical circuit and a single atom

March 30, 2012
Author(s)
Jacob M. Taylor, Dvir Kafri, David Kielpinski, G J. Milburn, M J. Woolley
… devices using the coupling between the motion of a single ion and the quantised electric field of the circuit. … coupling between the internal states of a single atomic ion and the electrical excitations of a superconducting … Ion traps, superconducting resonator, bulk acoustic waves …
Displaying 551 - 575 of 2538
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