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Search Publications by: James(Trey) Porto (Fed)

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Displaying 51 - 75 of 182

Pneumatically Actuated and Kinematically Positioned Optics Mounts

September 4, 2013
Author(s)
Roger C. Brown, Steven Olmschenk, Wu Saijun, Ari Dyckovsky, Robert Wyllie, James V. Porto
We present two complementary designs of pneumatically actuated and kinematically positioned optics mounts: one designed for vertical mounting and translation, the other designed for horizontal mounting and translation. The design and measured stability

Light polarization and quantum interference effects in unresolvable atomic lines: application to a precise measurement of the 6,7Li D2 lines.

March 7, 2013
Author(s)
Roger C. Brown, Saijun Wu, James V. Porto, Craig J. Sansonetti, Clayton Simien, Samuel M. Brewer, Joseph N. Tan, John D. Gillaspy
We characterize the effect of quantum interference of light scattering on the line shapes and measured line positions in atomic spectra. These effects occur when the excited state splittings are of order the excited state line widths, and represent an

Loop Structure Stability of a Double-Well-Lattice BEC

December 26, 2012
Author(s)
James V. Porto, Hoi-Yin Hui, Ryan Barnett, Sankar Das Sarma
In this work, we consider excited many-body mean-field states of bosons in a double-well optical lattice by investigating stationary Bloch solutions to the non-linear equations of motion. We show that, for any positive interaction strength, a loop

Dynamically Slowed Collapse of a Bose-Einstein Condensate with Negative Scattering Length

December 3, 2012
Author(s)
Karina K. Jimenez Garcia, Robert L. Compton, Yu-Ju Lin, James V. Porto, Ian B. Spielman
We rapidly change the scattering length a_s of a ^{87}Rb Bose-Einstein condensate by means of a Feshbach resonance, simultaneously releasing the condensate from its harmonic trapping potential. When a_s is changed from positive to negative, the subsequent

Absolute transition frequencies and quantum interference in a frequency comb based measurement of the 6,7Li D lines

July 6, 2011
Author(s)
Craig J. Sansonetti, Clayton Simien, John D. Gillaspy, Joseph N. Tan, Samuel M. Brewer, Roger C. Brown, Saijun Wu, James V. Porto
Optical frequencies of the D lines of 6,7Li were measured with a relative accuracy of 5x10-11 using an optical comb synthesizer. Quantum interference in the laser induced fluorescence for the partially-resolved D2 lines was found to produce polarization

Differential Light Shift Cancellation in a B-Field Insensitive Transition of 87Rb

February 11, 2011
Author(s)
Radu S. Chicireanu, Karl D. Nelson, Steven M. Olmschenk, Nathan Lundblad, A. Derevianko, James V. Porto
We demonstrate substantial cancellation of the differential light shift of a magnetic-field-insensitive microwave hyperfine (clock) transition in 87Rb atoms trapped in an optical lattice. Up to 95.5% of the differential light shift is cancelled while

Synthetic Electric and Magnetic Fields for Ultracold Neutral Atoms

January 1, 2011
Author(s)
William D. Phillips, Yu-Ju Lin, Robert L. Compton, Karina K. Jimenez Garcia, Abigail R. Perry, James V. Porto, Ian B. Spielman
We use Raman coupling between magnetic sublevels of a 87Rb Bose-Einstein condensate (BEC) to create an effective vector gauge field for the neutral atoms. They behave as if they were charged particles in a magnetic vector potential. With appropriate

Randomized Benchmarking of Atomic Qubits in an Optical Lattice

November 4, 2010
Author(s)
Steven M. Olmschenk, Radu S. Chicireanu, Karl D. Nelson, James V. Porto
We perform randomized benchmarking on neutral atomic quantum bits (qubits) confined in an optical lattice. Single qubit gates are implemented using microwaves, resulting in a measured error per randomized computational gate of 1.4(1) x 10−4 that is

Phases of a 2D Bose Gas in an Optical Lattice

September 9, 2010
Author(s)
Karina K. Jimenez Garcia, Yu-Ju Lin, James V. Porto, Ian B. Spielman
Ultra-cold atoms in optical lattices realize essential models in condensed matter physics. Like with most experiments with ultra-cold atoms, our Rubidium-87 Bose Einstein condensate is confined in a harmonic trapping potential that persists even when

Adiabatic Preparation of Many-Body States in Optical Lattices

June 22, 2010
Author(s)
James V. Porto, Anders Sorensen, Ehud Altman, Michael Gullans, Mikhail Lukin, Eugene Demler
We analyze a technique for the preparation of low entropy many-body states of atoms in optical lattices based on adiabatic passage. In particular, we show that this method allows preparation of strongly correlated states as stable highest energy states of