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Search Publications by Paul D. Lett

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Displaying 1 - 25 of 92

Spinor Dynamics in an Antiferromagnetic spin-1 Thermal Bose Gas

July 9, 2013
Hyewon K. Pechkis, Jonathan Wrubel, Arne Schwettmann, Paul Griffin, Ryan Barnett, Eite Tiesinga, Paul D. Lett
We present experimental observations of coherent spin-population oscillations in a cold thermal, Bose gas of spin-1 23Na atoms. The population oscillations in a multi-spatial-mode thermal gas have the same behavior as those observed in a single-spatial

Demonstration of Superluminal Images

June 19, 2012
Ryan T. Glasser, Ulrich Vogl, Paul D. Lett
Optical pulse propagation with group velocities larger than the speed of light in vacuum, c, or negative, have been demonstrated theoretically and experimentally in a variety of systems [1–5]. The anomalous dispersion required for generating “fast” light

Effect of Losses on the Performance of an SU(1,1) Interferometer

June 4, 2012
Alberto M. Marino, Neil V. Corzo Trejo, Paul D. Lett
We study the effect of losses on the phase sensitivity of the SU(1,1) interferometer for different configurations. We find that this type of interferometer is robust against losses that result from an inefficient detection system. This type of loss only

Stimulated Generation of Superluminal Light Pulses via Four-wave Mixing

April 26, 2012
Ryan T. Glasser, Ulrich Vogl, Paul D. Lett
We report on the four-wave mixing of superluminal pulses, in which both the injected and generated pulses involved in the process propagate with negative group velocities. Generated pulses with negative group velocities of up to vg = −c/880 are

Quantum Correlated Light Beams from NonDegenerate FourWave Mixing in an Atomic Vapor: the D1 and D2 Lines of ^85Rb and ^87Rb

September 3, 2009
Raphael C. Pooser, Alberto M. Marino, Vincent N. Boyer, Kevin M. Jones, Paul D. Lett
We present experimental results showing that quantum correlated light can be produced using non-degenerate, off-resonant, four-wave mixing (4WM) on both the D1 (795 nm) and D2 (780 nm) lines of ^85Rb and ^87Rb, extending earlier work on the D1 line of

Low Noise Amplification of a Continuous Variable Quantum State

June 29, 2009
Raphael C. Pooser, Alberto M. Marino, Vincent Boyer, Kevin M. Jones, Paul D. Lett
We present an experimental realization of a low-noise, universal, phase-insensitive optical amplifier using four-wave mixing interaction in hot Rb vapor. Performance near the quantum limit for a range of amplifier gains, including near unity, can be

Number Fluctuations and Energy Dissipation in Sodium Spinor Condensates

June 5, 2009
Yingmei Liu, Eduardo N. Gomez, Stephen E. Maxwell, Lincoln D. Turner, Eite Tiesinga, Paul D. Lett
We characterize fluctuations in atom number and spin populations in F = 1 sodium spinor condensates. The time evolution of the population fluctuations shows a maximum. We interpret this as evidence of a dissipation-driven separatrix crossing in phase space

Tunable Delay of Einstein-Podolsky-Rosen Entanglement

February 18, 2009
Alberto M. Marino, Raphael C. Pooser, Vincent Boyer, Paul D. Lett
Entanglement is an important quantum resource which displays correlations between two subsystems that are stronger than the ones that can be obtained classically. This makes it the basis for a number of applications, such as quantum information processing

Production of Entangled Images by Four-Wave Mixing

December 1, 2008
Alberto M. Marino, Vincent Boyer, Raphael C. Pooser, Paul D. Lett
One of the most important resources in quantum mechanics is entanglement, which is characterized by correlations stronger than the ones allowed classically. As a result, it is at the basis of applications such as quantum cryptography, quantum information

Strong Low-Frequency Quantum Correlations From a Four-Wave Mixing Amplifier

October 15, 2008
C F. McCormick, Alberto M. Marino, V Boyer, Paul D. Lett
Quantum-correlated light displays sub-classical noise fluctuations between frequency sidebands on a single beam (quadrature squeezing) or between the intensities or phases of different beams (two-mode squeezing). Exploiting this noise reduction can improve

Measuring Optical Tunneling Times using a Hong-Ou-Mandel Interferometer.

September 23, 2008
Sergey Polyakov, Alan L. Migdall, Paul D. Lett, David Papoular, Pierre Clade, Colin McCormick
We report a prediction for the delay measured in an optical tunneling experiment using Hong-Ou-Mandel (HOM) interference, taking into account the Goos-Hanchen shift generalized to frustrated total internal reflection situations. We precisely state

Delocalized Correlations in Twin Light Beams with Orbital Angular Momentum

August 29, 2008
Alberto M. Marino, Vincent Boyer, Raphael C. Pooser, Paul D. Lett, Kristin Lemons, Kevin Jones
We generate intensity-difference-squeezed Laguerre-Gauss twin beams carrying orbital angular momentum using 4-wave mixing (4WM) in a hot atomic vapor. The conservation of orbital angular momentum in the 4WM process is studied as well as the spatial

Entangled Images from Four-Wave Mixing

July 25, 2008
Vincent Boyer, Alberto M. Marino, Raphael C. Pooser, Paul D. Lett
Two beams of light can be quantum mechanically entangled through correlations of their phase and intensity fluctuations. For a pair of spatially extended image-carrying light fields, the concept of entanglement can be applied not only to the entire images

Violation of Cauchy-Schwarz Inequality in the Macroscopic Regime

June 10, 2008
Alberto M. Marino, V Boyer, Paul D. Lett
We have observed a violation of the Cauchy-Schwarz inequality in the macroscopic regime by more than 8 standard deviations. The violation has been obtained while filtering out only the low frequency noise of the quantum-correlated beams that results from

Ultraslow Propagation of Matched Pulses by Four-Wave Mixing in an Atomic Vapor

October 4, 2007
V Boyer, C F. McCormick, E Arimondo, Paul D. Lett
We have observed the ultraslow propagation of matched pulses in nondegenerate four-wave mixing in a hot atomic vapor. Probe pulses as short as 70 ns can be delayed by a tunable time of up to 40 ns with little broadening or distortion. During the

Spinor Dynamics in an Antiferromagnetic Spin-1 Condensate

August 16, 2007
A T. Black, Eduardo Gomez, Lincoln Turner, Sebastian Jung, Paul D. Lett
We observed coherent spin oscillations in an antiferromagnetic spin-1 Bose-Einstein condensate of sodium. The variation of the spin oscillations with magnetic field shows a clear signature of nonlinearity, in agreement with theoretical predictions that

Light Force in Ultracold Photoassociation

January 26, 2007
Eduardo Gomez, A T. Black, Lincoln Turner, Eite Tiesinga, Paul D. Lett
We study the time-resolved photoassociation of ultracold sodium in an optical dipole trap. The photoassociation laser excites pairs of atoms to molecular states of large total angular momentum at high intensities (above 20 kW/cm2). Such transitions are

All-Optical Generation and Photoassociative Probing of Sodium Bose-Einstein Condensates

May 2, 2006
R Dumke, M Johanning, Eduardo Gomez, J D. Weinstein, Kevin Jones, Paul D. Lett
We demonsatrate an all optical technique to evaporatively produce sodium Bose-Einsteincondensates (BEC). We use a crossed-dipole trap formed from light near 1 $\mu$m, and a simple ramp of the intensity to force evaporation. In addition, we introduce