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Frequency-stabilized cavity ring-down spectrometer for high-sensitivity measurements of water vapor concentration

August 12, 2006

Author(s)

Joseph Hodges, D Lisak

We present a portable spectrometer that uses the frequency-stabilized cavity ring-down spectroscopy technique to realize high-precision measurements of trace water vapor concentration. Measuring one of the strongest rovibrational transitions in the 1 + 3

Broadband coherent anti-strokes Raman spectroscopy characterization of polymer thin films

August 2, 2006

Author(s)

Lee J. Richter, M C. Gurau, Zachary Schultz

Broadband coherent anti-Stokes Raman spectroscopy (CARS) is demonstrated as an effective probe of the polymer thin film materials. A simple modification to a commercially available 1 kHz SFG spectrometer permits acquisition of CARS spectra for polymer thin

Fermi Level Alignment in Self-Assembled Molecular Layers: The Effect of Coupling Chemistry

August 1, 2006

Author(s)

Christopher D. Zangmeister, Steven W. Robey, Roger D. van Zee

Photoelectron spectroscopy was used to explore changes in Fermi level alignment, within the p-p* gap, arising from changes in the coupling chemistry of conjugated phenylene ethynlene oligomers to the Au surface. Self-assembled monolayers were formed

Round Robin Study of Arsenic Implant Dose Measurement in Silicon by SIMS

July 30, 2006

Author(s)

David S. Simons, Richard M. Lindstrom

Propagation of shape-preserving optical pulses in inhomogeneously broadened multi-level systems

July 12, 2006

Author(s)

Lu Deng, Guoxiang Huang, C Hang

We study stable propagation of multiple shape-preserving optical pulses in an inhomogeneously broadened multi-level atomic medium. By analytically solving the Maxwell-Schr¿odinger equations governing the evolution of N coupled optical fields and atomic

Natural Linewidth of the 401-nm Laser-Cooling Transition in Er I

June 20, 2006

Author(s)

Jabez McClelland

A measurement of the natural linewidth of the 401 nm 4f 126s 2 ( 3H 6) rarr} 4f 12( 3H)6s6p ( 1P o 1) (6,1) 7 o transition in Er I is presented. Using laser-induced fluorescence in an atomic beam, a linewidth of (36.0 plus or minus} 1.2) MHz is observed, a

Formation and propagation of coupled ultraslow optical soliton pairs in a cold three-state double- system

May 17, 2006

Author(s)

Lu Deng, M. G. Payne, Guoxiang Huang, kaijun Jiang

We investigate the simultaneous formation and propagation of coupled ultraslow optical soliton pairs in a cold, lifetime-broadened three-state double- atomic system. Starting from the equations of motion of atomic response and two-mode probe-control

Effects of multi-photon interferences from internally generated fields in strongly resonant systems

March 29, 2006

Author(s)

Lu Deng, M. G. Payne, W R. Garrett

In studies of various nonlinear optical phenomena, strong resonant features in the atomic or molecular response to multi-photon driven processes have been used to greatly enhance the visibility of otherwise weak higher- order processes. However, there are

Conformational Changes Associated With Receptor-Stimulated Guanine Nucleotide Exchange in a Heterotrimeric G-Protein a-Subunit: NMR Analysis of the GTPgS-Bound States

March 17, 2006

Author(s)

K D. Ridge, N G. Abdulaev, Xi-Cheng Zhang, T Ngo, D M. Brabazon, John P. Marino

Solution NMR studies of a 15N-labeled G-protein ?-subunit (G?) chimera (15N-ChiT) reconstituted heterotrimer have previously shown that binding of ??-subunits induces a pre-activated conformation in G? that may facilitate interaction with R* and guanine

Generalized nonlinear Schrodinger equation and ultraslow optical solitons in a cold four-state atomic system

March 13, 2006

Author(s)

Lu Deng, Guoxiang Huang, C Hang

We investigate the influence of high-order dispersion and nonlinearity on the propagation of ultraslow optical solitons in a lifetime broadened four-state atomic system under a Raman excitation. Using a standard method of multiple-scales we derive a

Highly efficient inelastic four-wave mixing using dual induced transparency and coherently prepared states

March 13, 2006

Author(s)

Lu Deng, M. G. Payne, Kaijun Jiang

We investigate a life time broadened and coherently prepared five-state system for multi-wave mixing processes. We show that very efficient wave mixing occurs, producing an unconventional mixing wave that has the characteristics of both conventional four

Frequency-Stabilized Cavity Ring-Down Spectrometer for High-Sensitivity Measurements of Water Vapor Concentration

January 1, 2006

Author(s)

Joseph T. Hodges, Daniel Lisak

Preparation and Structure of Low-Density, Flat-Lying Decanethiol Monolayer From the Densely-Packed, Upright Monolayer on Gold

January 1, 2006

Author(s)

Laura B. Picraux, Christopher D. Zangmeister, J Batteas

This study investigates the formation of low-density, flat-lying decanethiol chemisorbed on Au prepared by heating the surface covered with a densely-packed, upright monolayer to a surface temperature above the onset of desorption. We determined conditions

Intrinsic Wavelength Standard Absorption Bands in Holmium Oxide Solution for UV/Visible Molecular Absorption Spectrophotometry

November 1, 2005

Author(s)

David L. Duewer, John C. Travis, J. C. Acosta, G Andor, J Bastie, P. Blattner, C J. Chunnilall, S. C. Crosson, E. A. Early, F. Hengstberger, C. Kim, L. Liedquist, F Manoocheri, A. Mito, L.A. G. Monard, S Nevas, M. Nilsson, M Noel, A C. Rodriguez, A Ruiz, A. Schirmacher, M V. Smith, G. Valencia, N. van Tonder, Joanne C. Zwinkels

Order and Disorder in Alkyl Stationary Phases

June 1, 2005

Author(s)

Lane C. Sander, Katrice A. Lippa, Stephen A. Wise

Laser Cooling Transitions in Atomic Erbium

April 18, 2005

Author(s)

H Ban, M Jacka, James L. Hanssen, Joseph Reader, Jabez J. McClelland

We discuss laser cooling opportunities in atomic erbium, identifying five J rarr} J + 1 transitions from the 4f 126s 2 3H 6 ground state that are accessible to common visible and near-infrared continuous-wave tunable lasers. We present lifetime

Precise Determination of 6 Li Cold Collision Parameters by Radio-Frequency Spectroscopy on Weakly Bound Molecules

March 1, 2005

Author(s)

M Bartenstein, A Altmeyer, S Riedl, R Geursen, S Jochim, C Chin, J Hecker Denschlag, R Grimm, Andrea Simoni, Eite Tiesinga, Carl J. Williams, Paul S. Julienne

Radio-frequency spectroscopy on weakly bound 6Li_2 molecules determines to high precision the molecular binding energies and the energy splitting between molecular states. By fitting the measurement to a multi-channel quantum scattering model, we determine

Achieving induced transparency with one- and three-photon destructive interference in a two-mode, three-level, double-L system

January 28, 2005

Author(s)

Lu Deng, M G. Payne

We show that in a two-mode, three-level, double-L system an efficient multiphoton destructive interference involving one- and three-photon pumping pathways occurs, leading to a unique type of induced transparency. Unlike the conventional

Infrared and Raman Spectroscopy Characterization of Biological Products

January 1, 2005

Author(s)

Vytautas Reipa

Both infrared and Raman are increasingly applied in biomolecular structure characterization, thus getting acceptance alongside traditional bioanalytical techniques. Physical principles and biological sampling requirements are reviewed. Advanced

Ultrafast Transient THz Spectroscopy of Azobenzene

January 1, 2005

Author(s)

Okan Esenturk, Edwin J. Heilweil

Efficient multi-wave mixing in ultra slow propagation regime and the role of multi-photon quantum destructive interference,

October 1, 2004

Author(s)

Y Wu, M G. Payne, Edward W. Hagley, Lu Deng

We analyze a lifetime-broadened four-state four-wave-mixing (FWM) scheme in the ultraslow propagation regime and show that the generated FWM field can acquire the same group velocity and pulse shape as those of an ultraslow pump field. We show that a new

Fermi Level Alignment and Electronic Levels in Molecular Wire Self-Assembled Monolayers on Au

October 1, 2004

Author(s)

Christopher D. Zangmeister, Steven W. Robey, Roger D. van Zee, Yuxing Yao, J M. Tour

A combination of one- and two-photon photoelectron spectroscopies are used to determine the electronic structure around the Fermi level for self-assembled monolayers of a prototypical molecular wire , 4,4 -(ethynylphenyl)-1-benzenethiol (C6H5-C≡C-C6H4-C≡C-

Structure of Polystyrene at the Interface With Various Liquids

September 4, 2004

Author(s)

Clayton S. Yang, P T. Wilson, Lee J. Richter

Vibrationally resonant sum frequency generation (VR-SFG) is used to determine the structure of the phenyl side groups of deuterated polystyrene at the liquid/solid interface for the nonsolvent liquids: hexane, methanol, ethanol, glycerol, and water. The

Inelastic wave mixing and multi-photon destructive interference based induced transparency in coherently prepared media

September 1, 2004

Author(s)

Lu Deng, Marvin G. Payne, W R. Garrett

We consider a multi-level medium initially prepared with a coherent superposition of two initial levels that are not directly dipole-coupled. We study the production of multi-wave mixing in the coherent medium, where the process begins on one and

Ultra slow bright and dark optical solitons in a cold three-state medium,

September 1, 2004

Author(s)

Y Wu, Lu Deng

We show the formation of ultraslow bright and dark optical solitons in a lifetime-broadened three-state atomic system under Raman excitation. We also discuss why such ultraslow optical solitons may not exist under the conditions of the usual