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Arvind Balijepalli, Thomas W. LeBrun, Jason J. Gorman
We demonstrate an increase in trapping lifetime for optically trapped nanoparticles by more than an order of magnitude using feedback control. This has been demonstrated through simu- lation and experimental results for 100, nm gold particles and 350 nm
Galen C. O'Neil, Peter J. Lowell, Joel N. Ullom, Jason M. Underwood
In a refrigerator, heat is moved from one system to another and this movement requires an additional dissipated power. It is desirable to both isolate the cooled system, so that its temperature may differ from the bath, and to heatsink the heated system so
This Resource Letter provides a guide to the literature on the Spin-Statistics Connection and related issues such as the Pauli Exclusion Principle and particle indistinguishability. Journal articles and books are cited for the following topics: basic
Energies, lifetimes, and wave function compositions have been computed for all levels of 4p64d, 4p64f, and 4p54d2 using single- and double excitations from a multi-reference set (SD-MR) to generate expansions for the multiconfiguration Dirac-Hartree-Fock
A historical article about the origins and the development of radio controlled clocks (Part IV of a IV-part series). It describes the first time signal radio stations, the early use of telegraphic time codes, and the modern use of digital time codes. It
In this chapter we study the mechanisms for carrier transport in two dimensional graphene sheets. We demonstrate that at high carrier density, graphene's transport properties depend both on the type of impurities present and on graphene's screening
Jacob M. Taylor, Dvir Kafri, David Kielpinski, G J. Milburn, M J. Woolley
Atomic systems are remarkably well suited to storage and processing of quantum information. However, their properties are tightly constrained by physical law, causing difficulties in interfacing to optical or electronic devices. On the other hand, quantum
An InSb working standard radiometer, first calibrated at NIST in 1999 against a cryogenic bolometer, was recently calibrated against a newly developed low-NEP pyroelectric transfer standard detector. The pyroelectric transfer standard, which can operate at
Gabriel G. Ycas, Franklyn J. Quinlan, Scott A. Diddams, Steve Osterman, Chad F. Bender, Brandon Botzer, Lawrence W. Ramsey, Ryan Terrien, Suvrath Mahadevan, Stephen L. Redman
We describe and characterize a 25 GHz laser frequency comb based on a cavity-filtered erbium fiber mode-locked laser that provides a uniform array of optical frequencies stabilized using the GPS-system atomic clocks spanning 14751625 nm. This comb was
George P. Eppeldauer, Howard W. Yoon, Jinan Zeng, Thomas C. Larason, Jeanne M. Houston, Vladimir Khromchenko
The National Institute of Standards and Technology (NIST) is working to extend the upper wavelength limit of the spectral power-responsivity calibration service from 1800 nm to 2500 nm. This extension is based on extended-InGaAs (EIGA) transfer- and
This paper give the 2010 self-consistent set of values of the basic constants and conversion factors of physics and chemistry recommended by the Committee on Data for Science and Technology (CODATA) for international use. The 2010 adjustment takes into
I will show how the statistical models that are used to describe the performance of atomic clocks are derived from their internal design. These statistical models form the basis for time scales, which are used to define international time scales such as
The uncertainty in the realization and dissemination of the SI second is determined by the characteristics of three major components: (1) the primary frequency standards themselves, (2) the time scale fly wheels that provide a continuously present
Michael R. Vissers, Jeffrey S. Kline, Jiansong Gao, David S. Wisbey, David P. Pappas
Low loss TiN resonators were fabricated on 3" intrinsic Si substrates. By exploiting the etch rate anisotropy in a parallel plate reactive ion etch, otherwise identical coplanar waveguides with gaps of varying depth were created in the same TiN film within
Elizabeth A. Strychalski, Jon C. Geist, Michael Gaitan, Laurie E. Locascio, Samuel M. Stavis
Quantitative size measurements of single linear and circular DNA molecules in nanofluidic slitlike confinement are reported. A novel experimental method using DNA entropophoresis down a nanofluidic staircase implemented comprehensive variation of slitlike
Preparing molecules at rest and in a highly pure electronic, rotational and vibrational quantum state is a long standing dream in chemistry and physics, so far only achieved for a select set of molecules in experimental setups dedicated to that species
A. Cygan, D Lisak, S. Wojtewicz, J. Domyslawska, Joseph T. Hodges, R.S. Trawinski, R. Ciurylo
We present a new cavity-enhanced technique for the precise measurement of absorption line shape and line position. This approach, which combines high-bandwidth locking of a continuous wave probe laser with frequency-stabilized cavity ring-down spectroscopy
Scott A. Diddams, Stephen L. Redman, Gabriel G. Ycas, Ryan Terrien, Suvrath Mahadevan, Lawrence W. Ramsey, Chad F. Bender, Steve Osterman, Franklyn J. Quinlan, James E. Lawler, Gillian Nave
The rapid advance in near-infrared (NIR) detector technology in the past decade has lead to a number of high-resolution astronomical spectrometers that are either in operation or in the planning stages. Precision wavelength calibration techniques
Broadband UV measurements are analyzed when UV-A irradiance meters measure optical radiation from 365-nm sources. The CIE standardized rectangular-shape UV-A function can be realized only with large spectral mismatch errors. The spectral power-distribution
Energy levels, with designations and uncertainties, have been compiled for the spectra of strontium (Z=38) ions from singly-ionized to hydrogen-like. Wavelengths with classifications, intensities, and transition probabilities are also tabulated. In
A historical article about the origins and the development ofatomic clocks and oscillators (Part III of a IV-part series). It describes the first atomic clock experiments, early laboratory and commercial cesium clocks, and the transition from astronomical
Ritz wavelengths of 27 spectral lines of Fe II of have been derived from Fourier transform spectra. The lines selected are observable in absorption spectra from quasi-stellar objects and are important for astronomical tests of the invariance of the fine
Sukumar Rajauria, L. Pascal, P. Gandit, F. Hekking, B. Pannetier, H. Courtois
We have studied the di®usion of excess quasiparticles in a current-biased superconductor strip in proximity to a metallic trap junction. In particular, we have measured accurately the superconductor temperature at a near-gap injection voltage. By analyzing
We show how the Fourier transform of a shape in any number of dimensions can be simplified using Gauss' law and evaluated explicitly for polygons in two dimensions, polyhedra three dimensions, etc. We also show how this combination of Fourier and Gauss can
Alexander Kramida, C M. Brown, Uri Feldman, Joseph Reader
Spectra of Ne emitted by a Penning discharge were recorded in the extreme ultraviolet (EUV) region between 140 Å and 359 Å on a 10.7 m grazing-incidence spectrograph with phosphor storage image plates. These spectra provided 33 newly identified lines of Ne