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Search Publications

NIST Authors in Bold

Displaying 951 - 975 of 2503

Artificial gauge fields with ultracold neutral atoms

January 1, 2019
Author(s)
Ian B. Spielman, Victor Galitski, Gediminas Juzeliunas
Gauge fields are ubiquitous in nature. In the context of quantum electrodynamics, you may be familiar with the photon, that represents the dynamical gauge field mediating electromagnetic forces. In fact all elementary interactions are mediated by gauge

Nonlinear Response of Silicon Solar Cells

January 1, 2019
Author(s)
Behrang H. Hamadani, Andrew M. Shore, Howard W. Yoon, Mark Campanelli
We used an LED-array-based combinatorial flux addition method to explore the wavelength and the intensity-dependence of the spectral responsivity in silicon solar cells. Many types of silicon cells, whether mono- or multi-crystalline type, exhibit notable

Chip-scale atomic diffractive optical elements

December 31, 2018
Author(s)
Liron Stern, Douglas G. Bopp, Susan A. Schima, Vincent N. Maurice, John E. Kitching
Atomic systems have long provided a useful material platform with unique quantum properties. The efficient light-matter interaction in atomic vapors has led to numerous seminal scientific achievements including accurate and precise metrology 1-3 and

Evidence for multiple mechanisms underlying surface-electric field noise in ion traps

December 27, 2018
Author(s)
J. A. Sedlacek, J. Stuart, Daniel Slichter, C. D. Bruzewicz, R. McConnell, J. M. Sage, J. Chiaverini
Energetic ion bombardment, or ion milling, of ion-trap electrode surfaces has previously been shown to reduce electric-field noise, a limit to quantum-logic gate fidelity, generated by the surface. Here, using motional heating of a single trapped strontium

The Metrological Basis for MOBY

December 20, 2018
Author(s)
Bettye C. Johnson
The Marine Optical BuoY (MOBY) is a primary source of data for System Vicarious Calibration (SVC) of ocean color satellite sensors. I will present brief introduction to SVC followed by a short history of MOBY and the main features of its instrumentation

Time Synchronization over a Free-Space Optical Communication Channel

December 20, 2018
Author(s)
Isaac H. Khader, Laura C. Sinclair, William C. Swann, Hugo Bergeron, Nathan R. Newbury, Jean-Daniel Deschenes
Free space optical (FSO) communication channels are typically used to transmit high-speed data between sites over the air. Here we repurpose an FSO digital communication system and use it directly for two-way time transfer. We demonstrate real-time

Cooperative Dynamics in a Model DPPC Membrane Arise from Membrane Layer Interactions

December 19, 2018
Author(s)
Kiley Kennedy, Neha Shafique, Jack F. Douglas, Francis W. Starr
The dynamics of model membranes can be highly heterogeneous, especially in more ordered dense phases. Experimentally, monolayers are often studied as a model system to infer the properties of membranes. To better understand the origins of this

Combined error signal in Ramsey spectroscopy of clock transitions

December 18, 2018
Author(s)
V. I. Yudin, A. V. Taichenachev, M. Y. Basalaev, T. Zanon-Willette, Juniper Wren Y. Pollock, Moshe Shuker, Elizabeth Donley, John Kitching
We have developed a universal method to form the reference signal for the stabilization of arbitrary atomic clocks based on Ramsey spectroscopy that uses an interrogation scheme of the atomic system with two different Ramsey periods and a specially

Quantum optimal control of the dissipative production of a maximally entangled state

December 14, 2018
Author(s)
Karl P. Horn, Florentin Reiter, Yiheng Lin, Dietrich Leibfried, Christiane P. Koch
Entanglement generation can be robust against noise in approaches that deliberately incorporate dissipation into the system dynamics. The presence of additional dissipation channels may, however, limit fidelity and speed of the process. Here we show how

Diagonal Slice Four-Wave Mixing: Natural Separation of Coherent Broadening Mechanisms

December 13, 2018
Author(s)
Travis M. Autry, Geoffrey M. Diederich, Mark E. Siemens
We present an ultrafast coherent spectroscopy data acquisition scheme that samples slices of the time domain used in multidimensional coherent spectroscopy to achieve faster data collection than full spectra. We derive analytical expressions for resonance

Atomic clock performance beyond Earths gravitational limit

December 6, 2018
Author(s)
William F. McGrew, Xiaogang Zhang, Robert J. Fasano, Stefan A. Schaeffer, Kyle P. Beloy, Daniele Nicolodi, Roger C. Brown, N. Hinkley, G. Milani, Marco Schioppo, T. H. Yoon, Andrew D. Ludlow
The passage of time is tracked by counting oscillations of a suitable frequency reference (e.g., the number of revolutions of Earth around the sun or the number of swings of a pendulum of a grandfather clock). By referencing the oscillations arising from

Approximating vibronic spectroscopy with imperfect quantum optics

November 23, 2018
Author(s)
W.R. Clements, Jelmer Renema, Andreas Eckstein, Antonio A. Valido, Adriana Lita, Thomas Gerrits, Sae Woo Nam, Steven Kolthammer, Joonsuk Huh
We study the impact of experimental imperfections on a recently proposed protocol for performing quantum simulations of vibronic spectroscopy. Specifically, we propose a method for quantifying the impact of these imperfections, optimizing an experiment to

Recommended electron-impact excitation and ionization cross sections for Be I

November 23, 2018
Author(s)
FNU Dipti, Tapasi Das, klaus Bartschat, I Bray, D Fursa, O Zatsarinny, C Ballance, H-K Chung, Yuri Ralchenko
Analytic fits to the recommended electron-impact excitation and ionization cross sections for Be I are presented. The lowest 19 terms of configurations 2snl (n 4) and 2p2 terms below the first ionization limit are considered. The fits are based on the

Quantum Process Fidelity Bounds from Sets of Input States

November 21, 2018
Author(s)
Emanuel H. Knill, Karl H. Mayer
We investigate the problem of bounding the quantum process fidelity given bounds on the fidelities between target states and the action of a process on a set of pure input states. We formulate the problem as a semidefinite program and prove convexity of

AC stark shifts of dark resonances probed with Ramsey spectroscopy

November 16, 2018
Author(s)
James Wesley Y. Pollock, V. I. Yudin, Moshe Shuker, M. Y. Basalaev, A. V. Taichenachev, Xiaochi Liu, John E. Kitching, Elizabeth A. Donley
The off-resonant AC Stark shift for coherent population trapping (CPT) resonances probed with Ramsey spectroscopy is investigated experimentally and theoretically. Measurements with laser- cooled 87Rb atoms show excellent quantitative agreement with a

Hierarchically Patterned Elastomeric and Thermoplastic Polymer Films through Nanoimprinting and Ultraviolet Light Exposure

November 13, 2018
Author(s)
Jack F. Douglas, Ying Chen, Manish Kulkarni, Allan Marshall, Alamgir Karim, ZiLu Wang, Xiaoteng Wang, Abdullah Al-Enizi, Ahmed Elzatahry, Andrey V. Dobrynin
We develop a simple and generally applicable method to fabricate hierarchical interfacial patterns in elastomer and thermoplastic polymer films through a combination of nanoimprinting and UVO microlithography. Using this method, tunable and hierarchically

Optimizing linearity in high-speed photodiodes

November 7, 2018
Author(s)
Josue Davila-Rodriguez, X. Xie, J. Zang, Christian J. Long, Tara M. Fortier, Holly F. Leopardi, Takuma Nakamura, J. C. Campbell, Scott A. Diddams, Franklyn J. Quinlan
Analog photonic links require high fidelity, high speed optical-to-electrical conversion for applications such as radio-over-fiber, synchronization at kilometer-scale facilities, and low- noise electronic signal generation. Nonlinearity is a particularly

Tuning the Relaxation of Nanopatterned Polymer Films with Polymer-Grafted Nanoparticles: Observation of EntropyEnthalpy Compensation

November 6, 2018
Author(s)
Jack F. Douglas, Xiaoteng Wang, Sonal Bhadauriya, Ren Zhang, Praveen Pitliya, Dharmaraj Raghavan, Alamgir Karim
We show that the previously observed polymeric clustering of nanoparticles (NPs) with grafted chains within polymer matrices can be pattern-directed by nanoimprinting ultrathin nanocomposite films so that the NPs segregate to thicker film regions where
Displaying 951 - 975 of 2503
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