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The energy levels and observed spectral lines of neutral and singly ionized titanium atoms have been compiled. Tables of energy levels and spectral lines are generated for each stage. Experimental g-factors and leading percentages are included when
Elizabeth A. Donley, Tara C. Liebisch, Eric M. Blanshan, John E. Kitching
We have decelerated an atomic beam of 87 Rb using a stimulated-emission slowing technique that makes use of a bichromatic standing light wave of high intensity and increased the load rate into a small magneto-optical trap by up to a factor of 20. We
The Time and Frequency Bulletin provides information on performance of time scales and a varieth of broadcasts (and related information) to users of the NIST services.
The injection of a neutral beam into the core of magnetically confined plasmas is a foundation for various plasma diagnostics, including charge-exchange recombination spectroscopy, beam-emission spectroscopy and motional Stark effect diagnostics. We review
Francisco E. Becerra Chavez, Jingyun Fan, Gerald Baumgartner, Sergey V. Polyakov, Julius Goldhar, Jonathan Kosloski, Alan L. Migdall
We investigate a strategy for M-ary discrimination of nonorthogonal phase states with error rates below the homodyne limit. This strategy uses feed forward to update a reference field and Signal nulling for the state discrimination. We experimentally
Jason M. Underwood, Peter J. Lowell, Galen C. O'Neil, Joel N. Ullom
We have examined the role of the substrate on electron-phonon coupling in normal metal films of Mn-doped Al at temperatures below 1 K. Normal metal-insulator-superconductor junctions were used to measure the electron temperature in thin metal films as a
Till P. Rosenband, David Hume, Chin-Wen Chou, David R. Leibrandt, Michael J. Thorpe, David J. Wineland
Coherent control of trapped atomic ions has led to several recent advances in quantum information processing 1 and precision spectroscopy 2. A basic requirement for these and other quantum-metrology experiments is the ability to detect the state of an
John P. Nibarger, James A. Beall, Daniel T. Becker, Joseph W. Britton, Hsiao-Mei Cho, Anna E. Fox, Gene C. Hilton, Johannes Hubmayr, Dale Li, Kent D. Irwin, Jeffrey L. Van Lanen, Jeff McMahon, Ki Won Yoon
Silicon platelet corrugated feedhorn for cosmic microwave background (CMB) measurements in the mm wave (130 to 170 GHz) have been developed for deployment for the polarization sensitive upgrade to both the Atacama Cosmology Telescope (ACTpol) and the South
Upcoming experiments aim to produce high fidelity polarization maps of the cosmic microwave background. To achieve the required sensitivity, the Truce collaboration is developing monolithic, feedhorn coupled TES polarimeter arrays. In this scheme, dual
Haifeng (. Jiang, Jennifer A. Taylor, Franklyn J. Quinlan, Tara M. Fortier, Scott A. Diddams
Commercially available erbium-doped mode-locked fiber lasers are compact, robust, and suitable to be the frequency divider of an ultra-low phase noise photonic microwave generator. However, for a mode-locked fiber laser with repetition rate of a few
The mission of the International Council for Science : Committee on Data for Science and Technology (CODATA ) is to strengthen international science for the benefit of society by promoting improved scientific and technical data management and use. One of
Andrew D. Ludlow, Nathan D. Lemke, Jeffrey A. Sherman, Christopher W. Oates, G. Quemener, J. von Stecher, A.M. Rey
Recently, ρ-wave cold collisions were shown to dominate the density-dependent shift of the clock transition frequency in a 171Yb optical lattice clock. Here we demonstrate that by operating such a system at the proper excitation fraction, the cold
Dietrich G. Leibfried, Roman Schmied , Janus H. Wesenberg
We present a detailed study of quantum simulations of coupled spin systems in surface-electrode ion-trap arrays, and illustrate our findings with a proposed implementation of the hexagonal Kitaev model [A. Kitaev, Annals of Physics 321,2 (2006)]. The e
Peter J. Lowell, Galen C. O'Neil, Jason M. Underwood, Joel N. Ullom
Understanding the subgap behavior of Normal-Insulator-Superconductor (NIS) tunnel junctions is important in order to be able to accurately model the thermal properties of the junctions. Hekking and Nazarov developed a theory in which the NIS sub gap
Michael G. Tanner, Shellee D. Dyer, Burm Baek, Robert Hadfield, Sae Woo Nam
We demonstrate a distributed fiber Raman sensor for absolute temperature measurement with spatial resolution on the order of 1 cm at 1550 nm wavelength in single mode fiber using superconducting nanowire single photon detectors. Rapid measurements are
We report on the fabrication of high Q fused quartz microresonators and the generation of a frequency comb with 36 GHz mode spacing using them. We have characterized the intrinsic stability of the comb in both the time and frequency domains. Intensity
Shellee D. Dyer, Michael Tanner, Burm Baek, Robert Hadfield, Sae Woo Nam
We demonstrate a high-accuracy distributed fiber optic temperature sensor using superconducting nanowire single-photon detectors and single photon counting techniques. Our demonstration uses inexpensive single-mode fiber at standard telecommunications
Thomas Gerrits, Martin J. Stevens, Burm Baek, Brice R. Calkins, Adriana E. Lita, Scott C. Glancy, Emanuel H. Knill, Sae Woo Nam, Richard P. Mirin, Robert Hadfield, Ryan Bennink, Warren Grice, Sander N. Dorenbos, Tony Zijlstra, Teun Klapwijk, Val Zwiller
We characterize a pp-KTP crystal designed to produce pure single mode squeezed vacuum at 1570 nm. Measurements show a raw (corrected) Hong-Ou-Mandel interference with 86 % (90 %) visibility and a circular joint spectral probability distribution with a
David A. Howe, Danielle G. Lirette, Neil Ashby, Archita Hati, Craig W. Nelson
We create a measurement technique and metrics consistent with easy interpretation to be used in development of new oscillators specifically for applications in which the oscillators power is turned on and off. This is useful in predicting the performance
Paul D. Kunz, Vladislav Gerginov, Thomas P. Heavner, Steven R. Jefferts
We are developing a transportable rubidium (Rb) atomic fountain frequency standard which uses independently phase-locked diode lasers for laser-cooling. At this point in time, we have not demonstrated sub-Doppler (υKelvin) atom temperatures using out
John P. Lowe, Matthew J. Deutch, Glenn K. Nelson, Douglas D. Sutton, William C. Yates, Peder Hansen, Oren Eliezer, Tom Jung, Stephen Morrison, Yingsi Liang, Dinesh Rajan, Sidharth Balasubramanian, Arun Ramasami, Waleed Khalil
The WWVB broadcast of the time-code signal has not undergone major changes in its communications protocol and modulation scheme since its introduction in 1963. Its amplitude-modulation (AM) and pulse-width based representations of its digital symbols were
The National Institute of Standards and Technology (NIST) currently operates 35 public network time servers that are located at many different sites in the United States. The servers provide time messages over the public Internet in a number of different
We propose and demonstrate a novel technique to measure the vibration sensitivity of two-port fiber-based optical components. It uses a common-arm counter-propagating frequency-shifted interferometer that cancels the vibration induced phase noise of the
Andrew C. Wilson, Christian Ospelkaus, Aaron Vandevender, J. A. Mlynek, Kenton R. Brown, Dietrich G. Leibfried, David J. Wineland
We present a solid-state laser system that generates 750 mW of continuous-wave, single frequency, output at 313 nm. Sum-frequency generation with fiber lasers at 1550 nm and 1051 nm produces up to 2 W at 626 nm. This visible light is then converted to UV
Sukumar Rajauria, O. Ozsun, John R. Lawall, V. Yakhot, Kamil L. Ekinci
Inspiration for man-made superhydrophobic surfaces comes from Nature: the Lotus leaf [13], for instance, exploits superhydrophobicity to keep its surface dry and clean from contaminants. Superhydrophobicity emerges due to roughness on a chemically