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Search Publications by: Gretchen K Campbell (Fed)

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Displaying 1 - 25 of 41

Grating magneto-optical traps with complicated level structures

October 25, 2023
Author(s)
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

Accurate Determination of Hubble Attenuation and Amplification in Expanding and Contracting Cold-Atom Universes

February 28, 2022
Author(s)
Swarnav Banik, Monica Gutierrez Galan, Hector Sosa Martinez, 1, Madison Anderson, Stephen Eckel, Ian Spielman, Gretchen K. Campbell
In the expanding universe, relativistic scalar fields are thought to be attenuated by "Hubble friction," which results from the dilation of the underlying spacetime metric. By contrast, in a contracting universe this pseudofriction would lead to

Programmable System on Chip for controlling an atomic physics experiment

July 23, 2021
Author(s)
Ananya Sitaram, Gretchen K. Campbell, Alessandro Restelli
Most atomic physics experiments are controlled by a digital pattern generator used to synchronize all equipment by providing triggers and clocks. Recently, the availability of well-documented open-source development tools has lifted the barriers to using

Isotope shift spectroscopy of the 1S0 to 3P1 and 1S0 to 3P0 transitions in strontium

November 19, 2020
Author(s)
Gretchen K. Campbell, Hirokazu Miyake, Neal Pisenti, Peter Elgee, Ananya Sitaram
Isotope shift spectroscopy with narrow optical transitions provides a benchmark for atomic struc- ture calculations, and has also been proposed as a way to constrain theories predicting physics beyond the Standard model. Here, we have measured frequency

Confinement of an alkaline-earth element in a grating magneto-optical trap

October 15, 2020
Author(s)
Ananya Sitaram, Peter Elgee, Gretchen K. Campbell, Daniel Barker, Nikolai Klimov, Stephen Eckel
We demonstrate a compact magneto-optical trap (MOT) of alkaline-earth atoms using a nanofabricated diffraction grating chip. A single input laser beam, resonant with the broad 1S0 to 1P1 transition of strontium, forms the MOT in combination with three

A wide-bandwidth, high-power radio-frequency driver for acousto-optic and electro-optic devices

August 6, 2019
Author(s)
Daniel S. Barker, Neal C. Pisenti, Alessandro Restelli, Julia K. Scherschligt, James A. Fedchak, Gretchen K. Campbell, Stephen P. Eckel
We present a design for a general-purpose radio-frequency amplifier circuit that is suitable for driving acousto-optic and electro-optic devices. Our design uses telecom amplifiers to achieve power output > 1 W over a 10 MHz to 1.1 GHz frequency range, and

A supersonically expanding Bose-Einstein condensate: an expanding universe in the lab

April 19, 2018
Author(s)
Stephen P. Eckel, Avinash Kumar, Theodore Jacobson, Ian B. Spielman, Gretchen K. Campbell
We study the dynamics of a supersonically expanding Bose-Einstein ring condensate both experimentally and theoretically using simulations. Such expansion shows a redshift of long-wavelength excitations, similar to those seen in the standard cosmological

An ultra-low noise, high-voltage piezo driver

December 8, 2016
Author(s)
Neal C. Pisenti, Alessandro Restelli, Ben J. Reschovsky, Daniel Barker, Gretchen K. Campbell
We present an ultra-low noise, high-voltage driver suited for use with piezoelectric actuators and other low- current applications. The architecture uses a flyback switching regulator to generate up to 250V in our current design, with an output of 1 kV or

Contact resistance and phase slips in mesoscopic superfluid atom transport

June 15, 2016
Author(s)
Stephen Eckel, Jeffrey Lee, Fred Jendrejewski, Christopher Lobb, Gretchen K. Campbell, Wendell Hill
We have experimentally measured both resistive flow and superflow with bosonic atoms in a mesoscopic transport experiment. Our system, consisting of two Bose-Einstein condensates coupled by a narrow channel, shows resistive flow for currents above a

Minimally destructive, Doppler measurement of a quantized, superfluid flow

February 1, 2016
Author(s)
Avinash Kumar, Neil Anderson, William D. Phillips, Stephen P. Eckel, Gretchen K. Campbell, Sandro Stringari
The Doppler effect, the shift in the frequency of sound due to motion, is present in both classical gases and quantum superfluids. Here, we perform an in-situ, minimally destructive measurement, of the persistent current in a ring-shaped, superfluid Bose

Enhanced Magnetic Trap Loading for Atomic Strontium

October 26, 2015
Author(s)
Gretchen K. Campbell, Daniel Barker, Benjamin Reschovsky, Neal Pisenti
We report on a technique to improve the continuous loading of atomic strontium into a magnetic trap from a Magneto-Optical Trap (MOT). This is achieved by adding a depumping laser tuned to the 3 P1 → 3 S 1 (688-nm) transition. The depumping laser increases