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Daniel Barker, Peter Elgee, Ananya Sitaram, Eric Norrgard, Nikolai Klimov, Gretchen K. Campbell, Stephen Eckel
We study the forces and optical pumping within grating magneto-optical traps (MOTs) operating on transitions with non-trivial level structure. In contrast to the standard six-beam MOT configuration, rate equation modelling predicts that the asymmetric
Molecules have vibrational, rotational, spin-orbit and hyperfine degrees of freedom or quantum states, each of which responds in a unique fashion to external electromagnetic radiation. The control over superpositions of these quantum states is key to
We experimentally and theoretically investigate the anisotropic speed of sound of an atomic superfluid (SF) Bose-Einstein condensate in a 1D optical lattice. Because the speed of sound derives from the superfluid density, implying that this density is
John Kitching, Matthew Hummon, William McGehee, Ying-Ju Wang, Susan Schima
We describe work toward the development of next-generation chip-scale atomic clocks, which combine small size, low power consumption and manufacturability with high frequency stability. The use of optical transitions in microfabricated vapor cells improves
Electrical signals derived from optical sources have achieved record-low levels of phase noise, and have demonstrated the highest frequency stability yet achieved in the microwave domain. Attaining such ultrastable phase and frequency performance requires
Giovanni Garberoglio, Christof Gaiser, Roberto Maria Gavioso, Allan H. Harvey, Robert Hellmann, Bogumil Jeziorski, Karsten Meier, Michael R. Moldover, Laurent Pitre, Krzysztof Szalewicz, Robin Underwood
Recent advances regarding the interplay between ab initio calculations and metrology are reviewed, with particular emphasis on gas-based techniques used for temperature and pressure measurements. Since roughly 2010, several thermophysical quantities – in
Eric Norrgard, Catherine Cooksey, Stephen Eckel, Nickolas Pilgram, Kayla Rodriguez, Howard W. Yoon, Yuly Andrea Chamorro Mena, Lukas Pasteka, Anastasia Borschevsky
Here we report measured and calculated values of radiative decay rates and vibrational branching fractions for the A$^2\Pi$ state of MgF. The decay rate measurements use time-correlated single photon counting with roughly 1\,\% total uncertainty. Branching
Kayla Rodriguez, Nickolas Pilgram, Daniel Barker, Stephen Eckel, Eric Norrgard
We simulate the capture process of MgF molecules into a frequency-chirped molecular MOT. Our calculations show that by chirping the frequency, the MOT capture velocity is increased by about of factor of 4 to 80m/s, allowing for direct loading from a two
Drew Rotunno, Samuel Berweger, Nik Prajapati, Aly Artusio-Glimpse, MATTHEW SIMONS, chris holloway, Amy Robinson
We investigate the effects of spatially non-uniform radio-frequency electric (E) field amplitudes on the spectral line shapes of electromagnetically induced transparency (EIT) signals in Rydberg atomic systems used in electrometry (i.e., the metrology of E
Yang Yang, Dipti Dipti, Chihiro Suzukic, A. C. Gall, R. Silwal, Samuel Sanders, Joseph N. Tan, Aung S. Naing, Endre Takacs, Yuri Ralchenko
Extreme ultraviolet (EUV) radiation from M-shell Ca-like, Nd40+, through Nalike, Nd49+, highly charged ions have been measured at an electron beam ion trap (EBIT) facility at the National Institute of Standards and Technology. To produce the ionization
Nik Prajapati, Aly Artusio-Glimpse, Matt Simons, Samuel Berweger, Drew Rotunno, Maitreyi Jayaseelan, Kaleb Campbell, Christopher L. Holloway
Rydberg atoms show great promise for use as self-calibrated electric field sensors for a broad range of frequencies. Their response is traceable to the international system of units making them a valuable tool for a variety of applications including
Daniel Barker, James A. Fedchak, Jacek Klos, Julia Scherschligt, Abrar Sheikh, Eite Tiesinga, Stephen Eckel
We present measurements of thermalized collisional rate coefficients for ultra-cold $^7$Li and $^87}$Rb colliding with room-temperature He, Ne, N$_2$, Ar, Kr, and Xe. In our experiments, a combined flowmeter and dynamic expansion system, a vacuum metrology
Barry I. Schneider, luca argenti, Siddhartha Chattopadhyay, carlos marante, Jeppe Olsen
As a step toward the full ab-initio description of two-photon double ionization processes, we present a finitepulse version of the virtual-sequential model for polyelectronic atoms. The model relies on the ab initio description of the single ionization
Drew Rotunno, Nik Prajapati, Samuel Berweger, MATTHEW SIMONS, Aly Artusio-Glimpse, Amy Robinson, chris holloway
We present a thermal velocity sampling method for calculating Doppler-broadened atomic spectra, which more efficiently reaches a smooth limit than regular velocity weighted sampling. The method uses equal-population sampling of the 1-D thermal distribution
The continuing improvement in the qualities of photon-number-resolving (PNR) detectors opens new possibilities for measuring quantum states of light. In this work we consider the question of what properties of an arbitrary multi-mode Gaussian state are