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Fan Zhang, Andrew J. Allen, Lyle E. Levine, Gabrielle G. Long, Ivan Kuzmenko, Jan Ilavsky
We report a harmonic rejection scheme based on the combination of Si (111) monochromator and Si (220) harmonic-rejection crystal optics. This approach is of importance to a wide range of X- ray applications in all three major branches of modern X-ray
The National Institute of Standards and Technology (NIST) has offered and provided remote frequency and time calibration services to customers for more than three decades. These services continuously compare a customer's primary frequency and/or time
Abijith S. Kowligy, Daniel D. Hickstein, Alexander Lind, David Carlson, Henry R. Timmers, Nima Nader, Daniel Maser, Daron Westly, Kartik Srinivasan, Scott Papp, Scott Diddams
We demonstrate wide-band frequency down-conversion to the mid-infrared (MIR) using four-wave mixing (FWM) of near-infrared (NIR) femtosecond-duration pulses from an Er:fiber laser, corresponding to 100 THz spectral translation. Photonic-chip-based silicon
Nihar Pradhan, Carlos Garcia, Bridget Isenberg, Daniel Rhodes, Simin Feng, Shariar Memaran, Yan Xin, Amber McCreary, Angela R. Hight Walker, Aldo Raeliarijaona, Humberto Terrones, Mauricio Terrones, Steve McGill, Luis Balicas
We fabricated ambipolar field-effect transistors (FETs) from multi-layered triclinic ReSe2, mechanically exfoliated onto a SiO2 layer grown on p-doped Si. In contrast to previous reports on thin layers (2 to 3 layers), we extract field-effect carrier
Jack F. Douglas, Marat Andreev, Juan J. DePablo, Vivek Prabhu, Matthew Tirrell
Polyelectrolyte coacervation refers to the formation of distinct liquid phases that arise when polyelectrolytes are mixed under appropriate polymer and salt concentrations. Molecular-level studies of complex polyelectrolyte coacervation have been limited
Joshua J. Savory, Jeffrey A. Sherman, Stefania Romisch
The National Institute of Standards and Technology (NIST) is responsible for ensuring the quality of its international and domestic time and frequency distribution systems. Since the physical inputs to these systems are not collocated within the campus, an
Jonathan Wrubel, Arne Schwettmann, Donald P. Fahey, Glassmann Zachary, Heywon Pechkis, Paul Griffin, Ryan Barnett, Eite Tiesinga
The SU(1,1) interferometer was originally conceived as a Mach-Zehnder interferometer with the beam-splitters replaced by parametric amplifiers. The parametric amplifiers produce states with correlations that result in enhanced phase sensitivity. F = 1
Chip-scale atomic devices combine elements of precision atomic spectroscopy, silicon micromachining and advanced diode laser technology to create compact, low-power and manufacturable instruments with high precision and stability. We review the design
Andrew J. Metcalf, Tyler Anderson, Chad F. Bender, Wesley Brand, David Carlson, Scott Diddams, Connor Fredrick, S. Halverson, Daniel D. Hickstein, Fred Hearty, Jeffrey M. Jennings, Shubham Kanodia, Kyle Kaplan, Emily Lubar, Suvrath Mahadevan, Andrew Monson, Joe P. Ninan, Colin Nitroy, Scott Papp, L. Ramsey, Paul Robertson, Arpita Roy, Christian Schwab, Kartik Srinivasan, Gudmundur Stefansson, Ryan C. Terrien
We detail the first infrared precision astronomical spectroscopy results from the combination of an electro-optic laser frequency comb and the Habitable Zone Planet Finder spectrograph at the 10 m Hobby-Eberly telescope.
David R. Carlson, Daniel D. Hickstein, Wei Zhang, Andrew J. Metcalf, Franklyn J. Quinlan, Scott A. Diddams, Scott B. Papp
Optical frequency combs can produce femtosecond light pulses with sub-cycle precision, and are typically made by relying on the intrinsic stability of mode-locked lasers. Now, by carving a continuous-wave laser into pulses via electro-optic modulation (EOM
Jordan R. Stone, Travis Briles, Tara E. Drake, Daryl T. Spencer, David R. Carlson, Scott A. Diddams, Scott B. Papp
We report on radiofrequency techniques to reliably generate and control dissipative-Kerr- soliton microresonator frequency combs. Since the pump-laser frequency detuning to the resonator primarily determines the soliton dynamics, we devise an offset Pound
Zhiheng Jiang, Victor S. Zhang, Yi-Jiun Huang, Joseph Achkar, Dirk Piester, Shinn-Yan Lin, Wenjun Wu, Sung-hoon Yang, Jerzy Nawrocki, Ilaria Sesia, Christian Schlunegger, Zhiqiang Yang, Miho Fujieda, Albin Czubla, Hector Esteban, Carsten Rieck, Peter Whibberley
Two-Way Satellite Time and Frequency Transfer (TWSTFT) is a primary technique for the generation of Coordinated Universal Time (UTC). About 20 timing laboratories around the world continuously operate TWSTFT using the SAtellite Time and Ranging Equipment
Christine G. Pappas, Joseph W. Fowler, Douglas A. Bennett, William B. Doriese, Young I. Joe, Kelsey M. Morgan, Galen C. O'Neil, Joel N. Ullom, Daniel S. Swetz
Transition-edge sensor X-ray microcalorimeters are usually calibrated empirically, as the most widely-used calibration metric, optimal filtered pulse height (OFPH), in general has an unknown dependance on photon energy, E γ. Because the calibration
The fractional frequency comparison of clocks based on different atoms: hydrogen and cesium, is used to test one of the main postulates of general relativity to an accuracy five times better than previous tests. We compare the long-term fractional
Aruna N. Ramanayaka, Hyun Soo Kim, Joseph A. Hagmann, Roy E. Murray, Ke Tang, Neil M. Zimmerman, Curt A. Richter, Joshua M. Pomeroy, Frederick Meisenkothen, Huairuo Zhang, Albert Davydov, Leonid A. Bendersky
In pursuit of superconductivity in p-type silicon (Si), we are using a single atomic layer of aluminum (Al) sandwiched between a Si substrate and a thin Si epi-layer. The delta layer was fabricated starting from an ultra high vacuum (UHV) flash anneal of
An optical reference based on two-photon optical transition with AC stark shift cancellation is proposed. The reference uses two interrogating laser fields at different frequencies. Compared to conventional optical two-photon references, the new approach
The reversible binding of molecules to surfaces is one of the most important processes in condensed fluids, with the obvious applications in molecular separation of materials, chromatographic characterization, and material processing. Motivated in
Arghavan Safavi-Naini, R. J. Lewis-Swan, Justin G. Bohnet, M. Garttner, Kevin Gilmore, Elena Jordan, J. Cohn, James K. Freericks, Ana Maria Rey, John Bollinger
We use a self-assembled two-dimensional Coulomb crystal of ∼70 ions in the presence of an external transverse field to engineer a simulator of the Dicke Hamiltonian, an iconic model in quantum optics which features a quantum phase transition between a
David R. Carlson, Daniel D. Hickstein, Daniel C. Cole, Scott A. Diddams, Scott B. Papp
We experimentally demonstrate a versatile technique for performing dual-comb interferometry using a single frequency comb. By rapid switching of the repetition rate, the output pulse train can be delayed and heterodyned with itself to produce
Daniel C. Cole, Alessandra Gatti, Scott B. Papp, Franco Prati, Luigi Luigato
We derive a spatiotemporal equation describing nonlinear optical dynamics in Fabry-Perot (FP) cavities filled with a Kerr medium. This equation is an extension of the equation that describes dynamics in Kerr-nonlinear ring resonators, referred to as the