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Giuseppe Zibordi, Marko Talone, Kenneth Voss, B. Carol Johnson
Spectral resolution for in situ remote sensing reflectance (RRS) measurements supporting satellite ocean color validation and system vicarious calibration (SVC) are investigated to detail minimum requirements. The study, which is conducted using
Nathan Mahynski, Jeffrey R. Errington, Vincent K. Shen
We derive a method for extrapolating the grand canonical free energy landscape of a multicomponent fluid system from one temperature to another. Previously, we introduced this statistical mechanical framework for the case where kinetic energy contributions
Holly F. Leopardi, Josue Davila-Rodriguez, Franklyn J. Quinlan, Judith B. Olson, Scott A. Diddams, Tara M. Fortier
Laser frequency combs based on erbium-doped fiber mode-locked lasers have shown great potential for compact, robust and efficient optical clock comparisons. However, to simultaneously compare multiple optical clock species, fiber laser frequency combs
It is widely appreciated that an attractive polymer-substrate interaction can slow relaxation in thin supported polymer films and polymer nanocomposites. Recent measurements and simulations on nancomposites have indicated that this slowing of polymer
David R. Carlson, Daniel D. Hickstein, Alexander J. Lind, Judith B. Olson, Richard W. Fox, Roger C. Brown, Andrew D. Ludlow, Qing Li, Daron A. Westly, Tara M. Fortier, Kartik A. Srinivasan, Scott A. Diddams, Scott B. Papp
Supercontinuum generation using chip-integrated photonic waveguides is a powerful approach for spectrally broadening pulsed laser sources with very low pulse energies and compact form factors. When pumped with a mode-locked laser frequency comb, these
Daniel D. Hickstein, Hojoong Jung, David R. Carlson, Alexander J. Lind, Ian R. Coddington, Kartik A. Srinivasan, Gabriel G. Ycas, Daniel C. Cole, Abijith S. Kowligy, Stefan Droste, Erin S. Lamb, Nathan R. Newbury, Hong X. Tang, Scott A. Diddams, Scott B. Papp
Using aluminum-nitride photonic-chip waveguides, we generate optical frequency comb supercontinuum spanning 500~nm to 4000~nm, and show that the spectrum can be widely tailored by changing the geometry of the waveguide. Since aluminum nitride exhibits both
Jiuning Hu, David B. Newell, Jifa Tian, Nikolai N. Klimov, Tailung Wu, Yong Chen
We have fabricated bilayer-graphene double layers separated by a thin (~20 nm) boron nitride layer and performed Coulomb drag and counterflow thermoelectric transport measurements. The measured Coulomb drag resistivity is nearly three orders smaller in
We re-evaluated the relativistic redshift correction applicable to the frequency standards at the National Institute of Standards and Technology (NIST) in Boulder, Colorado, USA, based on a precise GPS survey of three benchmarks on the roof of the building
Gabriel A. Peterson, Florent Q. Lecocq, Katarina Cicak, Raymond W. Simmonds, Jose A. Aumentado, John D. Teufel
Abstract The ability to engineer nonreciprocal interactions is an essential tool in modern communication technology as well as a powerful resource for building quantum networks. Aside from large reverse isolation, a nonreciprocal device suitable for
Quenches in isolated quantum systems are currently a subject of intense study. Here, we con- sider quantum few-mode systems that are integrable in their classical mean-field limit and become dynamically unstable after a quench of a system parameter
We determined the outgassing rate of vacuum chambers constructed from common 304 stainless steel vacuum components. The vacuum components were assembled into identical vacuum chambers and subjected to either a medium temperature vacuum bake or a medium
Christopher D. Bass, Maynard S. Dewey, Thomas R. Gentile, Hans Pieter Mumm, Alan Keith Thompson, M J. Bales, R. Alarcon, E J. Beise, H Breuer, Jim Byrne, T E. Chupp, Kevin Coakley, R L. Cooper, B. O'Neill, F E. Wietfeldt
The theory of quantum electrodynamics predicts that a continuous spectrum of photons is emitted in the beta decay of the free neutron in addition to a proton, an electron, and an antineutrino. We report the first precision test of the shape of the photon
Kevin A. Gilmore, Justin G. Bohnet, Brian C. Sawyer, Joseph W. Britton, John J. Bollinger
We present measurements of the amplitude of a center-of-mass (COM) motion of a two-dimensional ion crystal composed of 100 ions in a Penning trap. For motion off-resonant with the trap axial frequency we demonstrate measurements of amplitudes as small as
Nicolas Marquez Peraca, D T. Bilir, Behrang Hamadani
The frequency dependence of the external quantum efficiency (EQE) of high-quality multijunction solar cells was examined by the modulated photocurrent spectroscopy method via an optical setup comprised of a light-pipe-coupled compact LED array. The optical
Eite Tiesinga, Alexander Petrov, Constantinos Makrides, Svetlana Kotochigova, Ming Li
We theoretically investigate trapping conditions for ultracold polar molecules in optical lattices, when external magnetic and electric fields are simultaneously applied. Our results are based on an accurate electronic-structure calculation of the polar
Vladislav P. Gerginov, Sean P. Krzyzewski, Svenja A. Knappe
A scalar magnetic field sensor based on 87Rb vapor millimeter-size cell is described. The magnetometer uses co-propagating pump/probe laser beam, amplitude modulation of the pump beam and non-demolition polarization rotation detection of the probe beam
Songbai Kang, Russell P. Mott, Kevin A. Gilmore, Logan D. Sorenson, Matthew T. Rahker, Elizabeth A. Donley, John E. Kitching, Christopher S. Roper
An electrically-controllable, solid-state, reversible device for sourcing and sinking alkali vapor is presented. When placed inside an alkali vapor cell, both an increase and decrease of the rubidium vapor density by a factor of two are demonstrated
David R. Carlson, Daniel D. Hickstein, Alexander J. Lind, Stefan Droste, Daron A. Westly, Nima Nader, Ian R. Coddington, Nathan R. Newbury, Kartik A. Srinivasan, Scott A. Diddams, Scott B. Papp
We utilize silicon nitride waveguides to self-reference telecom-wavelength fiber frequency combs through supercontinuum generation using less than 15 mW total optical average power. This is approximately ten times lower than conventional approaches using
Before atomic clocks, the second was defined by dividing astronomical events, such as the solar day or the tropical year, into smaller parts. This permanently changed in 1967, when the SI second was redefined as the duration of 9 192 631 770 energy
Martin Garttner, Justin G. Bohnet, Arghavan Safavi-Naini, Michael L. Wall, John Bollinger, Ana Maria Rey
Controllable arrays of ions and ultracold atoms can simulate complex many-body phenomena and may provide insights into unsolved problems in modern science. To this end, experimentally feasible protocols for quantifying the buildup of quantum correlations
Albert F. Rigosi, Nicholas R. Glavin, Chieh-I Liu, Yanfei Yang, Jan Obrzut, Heather M. Hill, Jiuning Hu, Hsin Y. Lee, Angela R. Hight Walker, Curt A. Richter, Randolph E. Elmquist, David B. Newell
Regarding the improvement of current quantized Hall resistance (QHR) standards, one promising avenue is the growth of homogeneous monolayer epitaxial graphene (EG). A clean and simple process was used to produce large, precise areas of EG. Properties like