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By codeposition of NO/Ne and O2/Ne mixtures at 6 K, weakly bound complexes between O2 and NO are formed. They exhibit a strong, structured charge transfer UV band at lambda(max) = 275 nm. The UV band disappears during UV irradiation of the neon matrix
Relativistic effects play an important role in the performance of the Global Positioning System (GPS) and in world-wide time comparisons. The GPS has provided a model for algorithms that take relativistic effects into account. In the future exploration of
Michael J. Biercuk, Hermann Uys, Aaron Vandevender, N. Shiga, Wayne M. Itano, David J. Wineland, John J. Bollinger
We demonstrate the efficacy of optimized dynamical decoupling pulse sequences in suppressing phase errors in a model quantum memory. Our experimental system consists of a crystalline array of trapped 9Be + ions in which we drive a qubit transition at $\sim
Jan Preusser, Svenja A. Knappe, John Kitching, Vladislav Gerginov
We present initial measurements of an atomic magnetometer in which the microfabricated sensor head is coupled to the control system by optical fibers. Since there are no electrical connections, the sensor head is largely non-magnetic and degradation of the
The performance of microwave components is sensitive to vibrations to some extent. Among them, microwave cables and connectors, bandpass filters, mechanical phase shifters and some nonlinear components are the most sensitive. The local oscillator is one of
Brad R. Blakestad, Aaron Vandevender, Christian Ospelkaus, Jason Amini, Joseph W. Britton, Dietrich G. Leibfried, David J. Wineland
Trapped ions are a useful system for studying the elements of quantum information processing. Simple alogrithms have been demonstrated, but scaling to much larter tasks requires the ability to manipulate many qubits. To achieve this, ions could be
G K. Campbell, M M. Boyd, J W. Thomsen, M J. Martin, S Blatt, M D. Swallows, Travis L. Nicholson, Tara Fortier, Christopher W. Oates, Scott Diddams, Nathan D. Lemke, Pascal Naidon, Paul S. Julienne, Jun Ye, Andrew Ludlow
At ultracold temperatures, the Pauli exclusion principle suppresses collisions between identical fermions. This has motivated the development of atomic clocks using fermionic isotopes. However, by probing an optical clock transition with thousands of
Mika Sillanpaa, Katarina Cicak, Fabio Altomare, Jae Park, Raymond Simmonds, Jian Li, G. S. Paraoanu, Pertti Hakonen
When a three-level quantum system is irradiated by an intense coupling field resonant with two of the three possible transitions, the resonant absorption of the system from its ground state by an additional radiation field is suppressed. This effect, where
N Poli, M.G. Tarallo, M. Schioppo, A. Alberti, Giorgio Ferrari, V. Ivanov, Christopher W. Oates, G.M. Tino
While existing optical lattice clocks demonstrate a high level of performance, they remain complex experimental devices. In order to address a wider range of applications including those requiring transportable devices, it will be necessary to simplify the
Jon H. Shirley, Thomas P. Heavner, Steven R. Jefferts
Many high performance atomic frequency standards, including cesium fountains and most optical standards, operate with pulsed measurements, that is, an atomic sample is prepared for measurement, the measurement is made, and the process is repeated at fixed
Matthew S. Kirchner, Danielle Braje, Tara M. Fortier, A.M. Weiner, Leo Hollberg, Scott A. Diddams
Optical filtering of a stabilized 1 GHz optical frequency comb produces a 20 GHz comb with ~40 nm bandwidth (FWHM) at 960 nm. Using a low finesse Fabry-Perot cavity in a double pass configuration provides a broad cavity coupling bandwidth (delta lambda
The SIM Time Network (SIMTN) has been one of the great success stories of the Sistema Interamericano de Metrologia (SIM), a regional metrology organization (RMO) that includes the 34 member nations of the Organization of American States (OAS). The SIMTN
Yu-Ju Lin, Robert L. Compton, Abigail R. Perry, William D. Phillips, James V. Porto, Ian B. Spielman
We use a two-photon dressing field to create an effective vector gauge potential for Bose-condensed ^87Rb atoms in the F=1 hyperfine ground state. The dressed states in this Raman field are spin and momentum superpositions, and we adiabatically load the
M Ledbetter, C.W. Crawford, A Pines, D.E. Wemmer, Svenja A. Knappe, John Kitching, D Budker
Nuclear magnetic resonance (NMR) has emerged as one of the most powerful analytical tools for elucidating molecular structure. One of the parameters typically extracted from NMR spectra which is necessary to fully understand the structure of a molecule is
We present catalogs of QSO candidates selected using photometry from GALEX combined with SDSS in the Stripe 82 region and Blanco Cosmology Survey (BCS) near declination −55 degrees. The SDSS region contains ≃ 700 ob jects with magnitude i
High-contrast coherent population trapping signal was observed on the Cs-D1 line using a bichromatic linear polarized light (lin||lin) field. The maximum absorption contrast of about 10% was obtained was nearly two times higher than that measured with the
Vincent Boyer, Alberto M. Marino, Raphael C. Pooser, Paul D. Lett
The entanglement properties of two beams of light can reside in subtle correlations that exist in the unavoidable quantum fluctuations of the amplitudes and the phases of the electric fields. Recent advances in the generation of nonclassical light with 4
Scott A. Diddams, Matthew S. Kirchner, Tara M. Fortier, Danielle Braje, A. M. Weiner, Leo W. Hollberg
We use a Fabry-Perot cavity to optically filter the output of a Ti:sapphire frequency comb to integer multiples of the original 1 GHz mode spacing. This effectively increases the pulse repetition rate which is useful for several applications. In the case
Hermann Uys, Michael J. Biercuk, Aaron Vandevender, N. Shiga, Wayne M. Itano, John J. Bollinger
We present a study of dynamical decoupling schemes for the suppression of phase erros due to various noise environments using ions in a Penning ion trap as a model ensemble of qubits. By injecting frequency noise we demonstrate that in an Ohmic noise
Hongyu Yu, Chuang-yuan Lee, Wei Pang, Hao Zhang, Alan Brannon, John E. Kitching, Eun Sok Kim
We have designed and built two oscillators, based on High-overtone Bulk Acoustic Resonators (HBAR) for application in Chip-Scale Atomic Clocks (CSAC). The measured phase noise of the 3.6-GHz oscillator is -67 dBc/Hz at 300 Hz offset and ?102 dBc/Hz at 10
We analyze the phase noise of the 20 GHz sub-picosecond optical pulse train generated by an optical frequency comb generator. The 10 fs for Fourier frequencies from 10 Hz to 10 residual timing jitter is MHz. Photodetection of the optical pulse train
Jeff C. Gust, Robert M. Graham, Michael A. Lombardi
Stopwatch and timer calibrations are perhaps the most common calibrations performed in the field of time and frequency metrology. Hundreds of United States laboratories calibrate many thousands of timing devices annually to meet legal and organizational
Brant Cage, James H. McNeely, Howard J. Halpern, Stephen E. Russek
The Finland trityl paramagnet is characterized by magnetic susceptibility and a new form of quantitative electron paramagnetic resonance (EPR) that utilizes a superconducting quantum interference device (SQUID) as a detection method. This radical is of
Elizabeth A. Donley, Jonathan Long, Tara C. Liebisch, Eleanor Hodby, Ted Fisher, John E. Kitching
We trace the transformation of I = 3/2 131-Xe nuclear spin resonances from the pure nuclear quadrupole regime to the quadrupole-perturbed Zeeman regime. We achieve large nuclear quadrupole shifts by using a 1mm 3 cubic cell with walls of different
William C. Griffith, Ricardo Jimenez Martinez, Vishal Shah, Svenja A. Knappe, John E. Kitching
A major limitation on the sensitivity of alkali atomic magnetometers, spin-exchange relaxation, can be completely eliminated by operating at low magnetic field and high alkali density. This allows the miniaturization of atomic magnetometers while retaining