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John E. Kitching, P. Ganssle, H Shin, Scott J. Seltzer, Vikram S. Bajaj, Micah P. Ledbetter, Dimitry Budkerl, Svenja A. Knappe, A Pines
In this work, we have demonstrated for the first time that an alkali vapor cell magnetometer has sufficient sensitivity to chemically resolve a heterogeneous mixture of oil and water by its relaxation and diffusion properties, both in one dimensional
We have made new observations of the spectrum of singly-ionized chromium (Cr II) in the region 2850 Angstrom to 37900 Angstrom with the National Institute of Standards and Technology 2 m Fourier transform spectrometer. These data extend our previously
Scott A. Diddams, Jiang Li, Xu Li, Hansuek Lee, Kerry J. Vahala
Optical frequency division using a mode-locked- laser, frequency comb has revolutionized time keeping and the generation of stable microwave signals. A different approach for optical frequency division and microwave generation using a comb of frequencies
Raymond W. Simmonds, Jie-Qiao Liao, Kurt Jacobs, Franco Nori
It is well-known that the nonlinear coupling between a mechanical oscillator and a superconducting oscillator or optical cavity can be used to generate a Kerr-nonlinearity for the cavity mode. We show that the strength of this Kerr-nonlinearity, as well as
A Peruzzi, J. van Geel, A. Uytun, M. Kalemci, E. Uysal, Gregory F. Strouse, Yoana Y. Nuevo Ordonez, William Davis
Water triple point cells are the basis for the definition of the Kelvin and for the realization of the International Temperature Scale of 1990. The temperature differences between the cells are mainly caused by impurities arising in the cell water from the
Joseph Reader, John D. Gillaspy, Dmitry D. Osin, Yuri Ralchenko
Extreme ultraviolet spectra of highly charged barium atoms were produced with an electron beam ion trap (EBIT) and recorded with a flat-field grazing-incidence spectrometer. The spectra were measured in the wavelength range 4 nm to 24 nm with the beam
Scott B. Papp, Katja M. Beha, Pascal P. Del'Haye, Franklyn J. Quinlan, Hansuek Lee, Kerry J. Vahala, Scott A. Diddams
Optical frequency combs enable measurement precision at the 20th digit, and measurement accuracy entirely commensurate with their reference oscillator. A new direction in experiments is the creation of ultracompact frequency combs by way of nonlinear
Dale J. Fixsen, Harvey Moseley, Thomas Gerrits, Adriana Lita, Sae Woo Nam
Design of TES microcalorimeters requires a tradeoff between resolution and dynamic range. Often, experimenters will require linearity for the highest energy signals, which requires additional heat capacity be added to the detector. This results in a
Angela R. Hight Walker, Alasdair Rae, Rainer Stosch, Petr Klapetek, Debdulal Roy
Raman spectroscopy is a powerful tool for the elucidation of qualitative and quantitative information from biological systems and has huge potential in areas such as biotechnologies, drug discovery, agro-chemical research and clinical diagnostics. This
Comparison of optical frequency measurements to predictions of quantum electrodynamics (QED) for Rydberg states of one-electron ions can test theory and allow new determinations of constants of nature to be made. Simplifications in the QED theory of high
Raju V. Datla , Michael Weinreb, Joseph P. Rice, B. Carol Johnson, Eric L. Shirley, Changyong Cao
This paper traces the cooperative effort of the scientists at the National Oceanic and Atmospheric Administration (NOAA) and the National Institute of Standards and Technology (NIST) for improving the calibration of operational satellite sensors for remote
We discuss frequency synthesizer needs and recent phase-noise results of a multi-level frequency divider that are consistent with phase noise of new high-accuracy optical atomic standards. Optical atomic standards achieve extremely low frequency
Adding Si2H6 or Si3H8 additives to SiH4/H2 discharges increases the growth rates for thin films of microcrystalline and amorphous silicon, but the reasons for this increase are not well understood. To better distinguish the chemical and physical from
Tian Zhong, Hongchao Zhou, Ligong Wang, Gregory Wornell, Zheshen Zhang, Jeffrey Shapiro, Franco N. Wong, Rob Horansky, Varun Verma, Adriana Lita, Richard Mirin, Thomas Gerrits, Sae Woo Nam, Alessandro Restelli, Joshua Bienfang, Francesco Marsili, Matthew Shaw
We demonstrate two high-dimensional QKD protocols - secure against collective Gaussian attacks - yielding up to 8.6 secure bits per photon and 6.7 Mb/s throughput, with 6.9 bits per photon after transmission through 20 km of fiber.
The literature of gas and liquid chromatography frequently contains schematic diagrams that depict analytical apparatus and peripherals. The interpretation of such diagrams can be facilitated by the following graphics that show the most common symbols used
In the interpretation of results from a particular technique, one often must evaluate the performance of the measurement on the basis of objective measures that are called figures of merit. The following table provides a description of the more common
Behrang H. Hamadani, John F. Roller, Andrew M. Shore, Brian P. Dougherty, Howard W. Yoon
An irradiance-mode absolute differential spectral response measurement system based on a light emitting diode (LED) array is described. The LEDs are coupled to an integrating sphere whose output irradiance is uniform to better than 2 % over an area of 160
Matthew Ruffoni, E. A. Den Hartog, James E. Lawler, N. R. Brewer, K. Lind, Gillian Nave, J C. Pickering
The Gaia-ESO Public Spectroscopic Survey (GES) is conducting a large-scale study of multielement chemical abundances of some 100; 000 stars in the Milky Way with the ultimate aim of quantifying the formation history and evolution of young, mature and
Cross-spectral analysis is a mathematical tool for extracting the power spectral density of a correlated signal from two time series in the presence of uncorrelated interfering signals. We demonstrate and explain a set of amplitude and phase conditions
We discuss techniques for measuring the correlation between phase modulated (PM) and amplitude modulated (AM) noise in an oscillator and report results of such correlation in a few selected oscillators of similar size, weight, power consumption and
Elizabeth A. Donley, Eric M. Blanshan, Francois-Xavier R. Esnault, John E. Kitching
A compact cold-atom clock based on coherent population trapping (CPT) has been developed. The clock typically demonstrates a short-term fractional frequency stability of 4x10 -11/√τ limited by frequency noise on the interrogation lasers. The largest two
Ricardo Jimenez Martinez, Daniel J. Kennedy, Michael Rosenbluh, Elizabeth A. Donley, Svenja A. Knappe, Scott J. Seltzer, Hattie L. Ring, Vikram S. Bajaj, John E. Kitching
We present a microfluidic chip that enables the production of laser-polarized 129Xe gas and its optical detection. Production of polarized 129Xe and its remote detection is achieved under flowing gas conditions at low magnetic fields in two separate
William Loh, Pascal P. Del'Haye, Scott B. Papp, Scott A. Diddams
We investigate the phase and coherence properties of microresonator combs using a combination of theoretical analysis, numerical simulation, and experimental measurement. Our analysis reveals that the comb phase in many cases does not stabilize to an