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Florent Q. Lecocq, Jeremy B. Clark, Raymond W. Simmonds, Jose A. Aumentado, John D. Teufel
We report the observation of efficient and low-noise frequency conversion between two microwave modes, mediated by the motion of a mechanical resonator subjected to radiation pressure. We achieve the coherent conversion of more than 10^{12} photons/s with
Zhiheng Jiang, Demetrios Matsakis, Victor S. Zhang, Hector Esteban, Dirk Piester, Shinn-Yan Lin
Two-Way Satellite Time and Frequency Transfer (TWSTFT) links were first introduced to the Coordinated Universal Time (UTC) generation in 1999 [1,19]. These TWSTFT links were calibrated by alignment with the corresponding GPS time links, of which the
I will report on a study of the usefulness of ARMA time scale algorithms to synchronize clocks on a digital network. The algorithm acquires periodic time differences between a local system clock and a remote time server by means of any of the standard
There is a need to back up critical timing infrastructure at the national level. This paper provides an update on a joint project employing commercial equipment to send national timing signals through a telecommunication network. This experiment connects
Jian Yao, Marc A. Weiss, Charles Curry, Judah Levine
This paper studies the impact of GPS jamming on GPS carrier-phase time transfer. To study this issue, at NIST, we have installed a commercial GPS jamming detector since 2014 April. During 2014 April 2015 April, the detector detected more than 100 jamming
We explore the nature of glass-formation in variable spatial dimensionality (d) based on the generalized entropy theory, a synthesis of the Adam-Gibbs model with direct computation of the configurational entropy of polymer fluids using an established
Kevin J. Coakley, Maynard S. Dewey, Michael G. Huber, Hans P. Mumm, Alan Keith Thompson, Andrew T. Yue, C. R. Huffer, P. R. Huffman, C. M. O'Shaughnessy, K. W. Schelhammer, D. E. Marley
In experiments that measure the lifetime of trapped particles, in addition to loss mechanisms with exponential survival probability functions, particles can be lost by mechanisms with non-exponential survival probability functions. Failure to account for
A B-spline version of a general Dirac-Hartree-Fock program is described. The usual differential equations are replaced by set of generalized eigenvalue problems of the form (Ha . åa B)Pa = 0, where Pa designates the two-component relativistic orbital in B
The spectrum of five-times-ionized zirconium Zr VI was observed from 160 Å to 2000 Å with sliding spark discharges on 10.7-m normal- and grazing-incidence spectrographs. The existing analysis of this spectrum [Khan Z. A. et al. 1985 Phys. Scr. 31 837] was
The Time and Frequency Bulletin provides information on performance of time scales and a variety of broadcasts (and related information) to users of the NIST services
We describe a general purpose digital servo optimized for feedback control of lasers in atomic, molecular, and optical (AMO) physics experiments. The servo is capable of feedback bandwidths up to roughly 1~MHz; loop filter shapes up to fifth order
Dina Genkina, Lauren M. Aycock, Hsin I Lu, Ian B. Spielman, Benjamin K. Stuhl
We directly measured the s-wave scattering cross-section of ultracold 40K atoms across the 20.2 mT Feshbach resonance by colliding pairs of degenerate Fermi gases (DFGs) and imaging the scattered atoms. Owing to DFGs low density, few atoms scattered, even
Ting Rei Tan, John P. Gaebler, Yiheng Lin, Yong Wan, Ryan S. Bowler, Dietrich G. Leibfried, David J. Wineland
Precision control over hybrid physical systems at the quantum level is of general importance in physics. For trapped-ions, a hybrid system formed of different species introduces extra degrees of freedom that can be exploited to expand and refine the
Lynden K. Shalm, Evan Meyer-Scott, B. G. Christensen, Peter L. Bierhorst, Michael A. Wayne, Deny Hamel, Martin J. Stevens, Thomas Gerrits, Scott C. Glancy, Michael S. Allman, Kevin J. Coakley, Shellee D. Dyer, Adriana E. Lita, Varun B. Verma, Joshua C. Bienfang, Alan L. Migdall, Yanbao Zhang, William Farr, Francesco Marsili, Matthew D. Shaw, Jeffrey Stern, Carlos Abellan, Waldimar Amaya, Valerio Pruneri, Thomas Jennewein, Morgan Mitchell, P. G. Kwiat, Richard P. Mirin, Emanuel H. Knill, Sae Woo Nam
We present a loophole-free violation of local realism using entangled photon pairs. We ensure that all relevant events in our Bell test are spacelike separated by placing the parties far enough apart and by using fast random number generators and high
P. Jonsson, L Radziute, G. Gaigalas, M. Godefroid, J P. Marques, T Brage, Charlotte F. Fischer, I. P. Grant
Multiconfiguration Dirac-Hartree-Fock (MCDHF) calculations and relativistic configuration interaction (RCI) calculations are performed for states of the 3s23p2, 3s3p3 and 3s23p3d configurations in the Si-like ions Ti IX - Ge XIX, Sr XXV, Zr XXVII, Mo XXIX
Studies and calibrations of short-lived radionuclides, for example 15O, are of particular interest in nuclear medicine. Yet counting experiments on such species are vulnerable to an error due to the combined effect of decay and dead time. Separate decay
Young Il Joe, Galen C. O'Neil, Luis Miaja Avila, Joseph W. Fowler, Kevin L. Silverman, Daniel S. Swetz, Joel N. Ullom, Ralph Jimenez
X-ray emission spectroscopy (XES) is a powerful probe of the electronic and chemical state of elemental species embedded within more complex compounds. X-ray sensors that combine high resolving power and high collecting efficiency are desirable for photon
In this work, scanning near-field microwave imaging was implemented to test the feasibility of the approach for in situ studies of nanosclale objects immersed in liquids under thin dielectric membranes. It was found that mechanical strength and stability
We investigate a method for entangling two singlet-triplet qubits in adjacent double quantum dots via capacitive interactions. In contrast to prior work, here we focus on a regime with strong interactions between the qubits. The interplay of the
Yilin Yu, Yifei Yu, Yongqing Cui, Wei Li, Gurarslan Alper, Peelaers Hartwin, Aspnes David, Chris Van de Walle, Nhan Van Nguyen, Zhang Yong-Wei, Linyou Cao
The control of photons by field effects, like the gating of electrons, can revolutionize a wide range of fields by enabling active photonic devices whose functions could be manipulated with sophistication and speeds comparable to what achieved in modern
The recently developed Flory-Huggins (FH) type general theory for competitive solvation of polymers by two mixed solvents is extended to explain phase boundaries and the variation of the solvent quality, as determined by the second osmotic virial coefficient
A superconducting transition edge sensor (TES) can be a useful tool for counting the number of photons in a highly attenuated pulse of light, but it requires calibration for its outputs to be interpretable as photon numbers. The Poisson-Influenced K-Means
Photons are not conserved in interactions with other matter. Consequently, when understanding the equation of state and thermodynamics of photons, while we have a concept of temperature for energy conservation, there is no equivalent chemical potential for
Thomas J. Silva, Justin M. Shaw, Hans T. Nembach, Mathias Weiler, Martin Schoen
The damping α of the spinwave resonances in 75 nm, 120 nm, and 200 nm -thick Permalloy films is measured via vector-network- analyzer ferromagnetic-resonance (VNA-FMR). Inductive coupling between the sample and the waveguide leads to an additional
Aric W. Sanders, Kavita M. Jeerage, Cindi Schwartz, Alexandra Curtin, Ann C. Chiaramonti Debay
Many proposed biomedical applications for engineered gold nanoparticles require their incorporation by mammalian cells in specific numbers and locations. Here, the number of gold nanoparticles inside of individual mammalian stem cells was characterized