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

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Displaying 26 - 50 of 182

Optical lattice with torus topology

September 26, 2018
Author(s)
Hwanmun Kim, Guanyu Zhu, James V. Porto, Mohammad Hafezi
We propose an experimental scheme to construct an optical lattice where the atoms are confined to the surface of a torus. This construction can be realized with spatially shaped laser beams which could be realized with recently developed high resolution

Bose Condensation of Photons Thermalized via Laser Cooling of Atoms

August 31, 2018
Author(s)
Chiao Wang, Michael Gullans, James V. Porto, William D. Phillips, Jacob Taylor
A Bose-Einstein condensate (BEC) is a quantum phase of matter achieved at low temperatures.Photons, one of the most prominent species of bosons, do not typically condense due to the lackof a particle number-conservation. We recently described a photon

Photon thermalization via laser cooling of atoms

July 19, 2018
Author(s)
Chiao-Hsuan Wang, Michael Gullans, James V. Porto, William D. Phillips, Jacob Taylor
The cooling of atomic motion by scattered light enables a wide variety of technological and scientific explorations. Here we focus on laser cooling from the perspective of the light — specifi- cally, the scattering of light between different optical modes

A low-steering piezo-driven mirror

July 18, 2018
Author(s)
Eric Magnan, James Maslek, Carlos Bracamontes-Palma, Alessandro Restelli, Thomas Boulier, James V. Porto
We present a piezo-driven translatable mirror with excellent pointing stability, capable of driving at frequencies up to tens of kilohertz. Our system uses a tripod of piezo actuators with independently controllable drive voltages, where the ratios of the

Dark state optical lattice with sub-wavelength spatial structure

February 20, 2018
Author(s)
Sarthak Subhankar, Tsz-Chun Tsui, James V. Porto, Steve Rolston, Przemek Bienias, Alexey Gorshkov, Mateusz Lacki, Michael Baranov, Peter Zoller
We report on the experimental realization of a conservative optical lattice for cold atoms with sub-wavelength spatial structure. The potential is based on the nonlinear optical response of three- level atoms in laser-dressed dark states, which is not

Spontaneous avalanche dephasing in large Rydberg ensembles

November 13, 2017
Author(s)
Thomas L. Boulier, Eric Magnan, Carlos Bracamontes, James Maslek, Elizabeth Goldschmidt, Jeremey Young, Alexey Gorshkov, Steven Rolston, James V. Porto
Strong dipole-exchange interactions due to spontaneously produced contaminant states can trigger rapid dephasing in many-body Rydberg ensembles [E. Goldschmidt et al., PRL 116, 113001 (2016)]. Such broadening has serious implications for many proposals to

Quantum and Classical Dynamics of BEC in a Large-Period Optical Lattice

April 4, 2016
Author(s)
Ian B. Spielman, Johnny H. Huckans, Bruno Laburthe-Tolra, James V. Porto, William D. Phillips
We experimentally investigate diffraction of a ^u87 Rb Bose-Einstein Condensate from a 1D optical lattice. We use a range of lattice periods and timescales, including those beyond the Raman-Nath limit. We compare the results to quantum mechanical and

Anomalous broadening in driven dissipative Rydberg systems

March 16, 2016
Author(s)
Elizabeth A. Goldschmidt, Thomas L. Boulier, Roger C. Brown, Silvio B. Koller, Jeremy T. Young, Alexey V. Gorshkov, S L. Rolston, James V. Porto
We observe interaction-induced broadening of the two-photon 5s-18s transition in 87Rb atoms trapped in a 3D optical lattice. The measured linewidth increases by nearly two orders of magnitude with increasing atomic density and excitation strength, with

Degenerate Bose-Fermi mixtures of rubidium and ytterbium

October 5, 2015
Author(s)
James V. Porto, Varun Vaidya, Jiraphat Tiamsuphat, Steven Rolston
We report the first realization of a quantum degenerate mixture of bosonic $^{87}$Rb and fermionic $^{171}$Yb atoms in a hybrid optical dipole trap with a tunable, species-dependent trapping potential. $^{87}$Rb is shown to be a viable refrigerant for the

Superexchange mediated magnetization dynamics in a 2D checkerboard optical lattice

May 1, 2015
Author(s)
Elizabeth A. Goldschmidt, Roger C. Brown, Silvio B. Koller, Michael S. Foss-Feig, James V. Porto, Robert Wyllie
The interplay of spin and motion underlies some of the most intriguing and poorly understood behaviors in many-body quantum systems. A well known example is the onset of superconductivity in cuprate compounds when mobile holes are introduced into an

Magic wavelengths for the 5s-18s transition in rubidium

March 30, 2015
Author(s)
Elizabeth A. Goldschmidt, Roger C. Brown, James V. Porto, Robert Wyllie, Silvio B. Koller, M S. Safronova, Ulyana I. Safronova, David Norris
Magic wavelengths, for which there is no differential ac Stark shift for the ground and excited state of the atom, allow trapping of excited Rydberg atoms without broadening the optical transition. This is an important tool for implementing quantum gates