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Search Publications by: Gretchen K Campbell (Fed)

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Displaying 26 - 41 of 41

Interferometric Measurement of the Current-Phase Relationship of a Superfluid Weak Link

September 22, 2014
Author(s)
Stephen Eckel, Fred Jendrzejewski, Avinash Kumar, Christopher J. Lobb, Gretchen K. Campbell
Weak connections between superconductors or superfluids differ from classical links due to quantum coherence, which allows flow without resistance. Transport properties through such weak links can be described with a single function, the current-phase

Resistive Flow in a Weakly Interacting Bose-Einstein condensate

July 25, 2014
Author(s)
Fred Jendrzejewski, Stephen P. Eckel, Noel Murray, Calib Lanier, Mark Edwards, Christopher J. Lobb, Gretchen K. Campbell
We report the direct observation of resistive flow through a weak link in a weakly interacting atomic Bose- Einstein condensate (BEC). Two weak links separate our ring-shaped superfluid atomtronic circuit into two distinct regions, a source and a drain

Hysteresis in Quantized Superfluid Atomtronic Circuit

February 14, 2014
Author(s)
Stephen P. Eckel, Jeffrey Lee, Fred Jendrzejewski, Noel Murray, Charles W. Clark, Christopher J. Lobb, William D. Phillips, Edwards Mark, Gretchen K. Campbell
Atomtronics is an emerging interdisciplinary field that seeks new functionality by creating devices and circuits where ultra-cold atoms play a role analogous to the electrons in electronics. Hysteresis in atomtronic circuits may prove to be a crucial

Driving Phase Slips in a Superfluid Atom Circuit with a Rotating Weak Link

January 10, 2013
Author(s)
Kevin C. Wright, William D. Phillips, Gretchen K. Campbell
We have induced well-defined phase slips between quantized persistent current states around a toroidal atomic 23Na Bose-Einstein condensate by rotating a weak link (a localized region of reduced superfluid density) around the ring at low angular frequency

Partial-Transfer Absorption Imaging: A versatile technique for optimal imaging of ultracold gases

August 13, 2012
Author(s)
Gretchen K. Campbell, Sergio R. Muniz, Kevin Wright, Russell P. Anderson, William D. Phillips, Kristian Helmerson
Partial-transfer absorption imaging is a tool that enables optimal imaging of atomic clouds for a wide range of optical depths. In contrast to standard absorption imaging, the technique can be minimally-destructive and can be used to obtain multiple

Superfluidity Goes 2D

August 13, 2012
Author(s)
Gretchen K. Campbell
In two-dimensional systems, superfluidity occurs in the absence of the long-range order associated with Bose-Einstein condensates. This phenomenon is illustrated in the direct observation of superfluidity in a two-dimensional atomic Bose gas.

Ultracold Atoms and Precise Time Standards

September 19, 2011
Author(s)
Gretchen K. Campbell, William D. Phillips
Experimental techniques of laser cooling and trapping, along with other cooling techniques have produced gaseous samples of atoms so cold that they are, for many practical purposes, in the quantum ground state of their center-of-mass motion. Such low

Superflow in a Toroidal Bose-Einstein Condensate: An Atom Circuit with a Tunable Weak Link

March 28, 2011
Author(s)
Kevin C. Wright, Anand Ramanathan, Sergio R. Muniz, Wendell Hill, Kristian Helmerson, William D. Phillips, Gretchen K. Campbell, Christopher Lobb
We have created a long-lived (40 s) persistent current in a toroidal Bose-Einstein condensate held in an all-optical trap. A repulsive optical barrier creates a tunable weak link in the condensate circuit, which can affect the current around the loop