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Tung T. To, Edwin J. Heilweil, Duke Charles, Ruddick Kristie, Webster E. Charles, Burkey Theodore
We review recent studies of processes relevant to photoinduced linkage isomerization of organometallic systems with the goal of preparing organometallics with an efficient and ultrafast photochromic response. The organometallic system thus corresponds to
James E. Maslar, Wilbur S. Hurst, Walter J. Bowers Jr., Jay H. Hendricks
Alloy 600 coupons were exposed to air-saturated water at pressures of 15.65 MPa and 25.4 MPa and temperatures ranging from 21 C to 543 C in an optically accessible flow cell. In situ Raman spectra were collected at a number of temperatures, as the metal
Polybrominated diphenyl ethers (PBDEs) are widely-used as flame retardants in electronic devices and upholstery. These are mobile in the environment, persistent, and bioaccumulative and are frequently found at low (pg/g) concentrations in many
Phonon-plasmon coupled mode Raman spectra of n-type GaSb were measured at room temperature as a function of electron concentration. These spectra were obtained using an optical system based on 752.55 nm excitation. Utilization of this wavelength permits
We make a detailed study on the dynamics of gain-assisted superluminal optical solitons in a three-state active-Raman-gain medium at room temperature. Using a method of multiple-scales we derive a high-order nonlinear Schrödinger equation with correction
In this work we present a brief review of recent results for water line shapes obtained by means of the frequency stabilized cavity ring-down spectroscopy (FS-CRDS) technique. We demonstrate its ability to enable precise spectroscopic measurements of
Ian R. Coddington, William C. Swann, Nathan R. Newbury
The output of a femtosecond fiber laser can be both spectrally broadened and stabilized, thereby providing a broadband coherent source in the near infrared. In the frequency domain, the result is a frequency comb with frequency stabilities at the
Ian R. Coddington, William C. Swann, Nathan R. Newbury
A stabilized frequency comb provides a broadband array of highly resolved comb lines. Using a multiheterodyne technique, we measure the amplitude and phase of every comb line, allowing for massively parallel, high-resolution spectroscopy.
Paul C. DeRose, Melody V. Smith, Klaus Mielenz, Douglas H. Blackburn, Gary W. Kramer
Standard Reference Material (SRM) 2941 is a cuvette-shaped, uranyl-ion-doped glass, recommended for use for relative spectral correction of emission and day-to-day performance validation of fluorescence spectrometers. Properties of this standard that
We show the possibility of generating gain-assisted superluminal optical solitons in a room- temperature three-state active Raman gain medium. We demonstrate both analytically and numerically that under appropriate conditions a signal field of very low
J A Rodriguez, Daniel Adler, P C Brand, Collin L. Broholm, Jeremy Cook, Christoph Brocker, R Hammond, Z Huang, P Hundertmark, J W Lynn, N C Maliszewskyj, J Moyer, J Orndorff, Donald J. Pierce, T D Pike, G Scharfstein, S A Smee, Rodrigo Vilaseca
We describe a novel cold neutron spectrometer under development at NIST optimized for wave vector resolved spectroscopy with incident energies between 2.1 meV and 20 meV and energy resolution from 0.05 meV (Ei = 2.1 meV) to 3.0 meV (Ei = 20 meV). By using
We report the first direct comparison of relative carrier mobilities in semiconducting organic polymer films measured using non-contact optical pump terahertz probe spectroscopy to those reported in electrical device studies. Relative transient signal
Room temperature p-type GaSb bulk coupled mode spectra were measured as a function hole concentration. These spectra were obtained using an optical system based on 752.55 nm excitation in order to obtain more sensitivity to bulk GaSb coupled mode
D J. Robichaud, Joseph T. Hodges, D Lisak, Charles E. Miller, Mitchio Okumura
We describe a high-precision method for measuring pressure shifting of absorption lines. The technique involves the acquisition of high-resolution spectra using a cavity ring-down spectrometer whose length is continuously locked to a frequency-stabilized
We present a new and simple approach to broadband coherent anti-Stokes Raman scattering (CARS) microscopy that yields background-free vibrational spectra. We present evidence for a mechanism where two different frequency components in a continuum pulse
The interpretation of Raman spectra of GaSb can be complicated by the presence of a so-called surface space-charge region (SSCR), resulting in an inhomogeneous near-surface Raman scattering environment. To fully interpret Raman spectra, it is important to
Using a single-channel active Raman gain medium, we show a 220±20 ns advance time for an optical pulse of FWHM=15.4 s propagating through a 10 cm medium, a lead time that is comparable to what was reported previously using a two-mode pump field. In
Christopher D. Zangmeister, Laura B. Picraux, Roger D. van Zee, Yuxing Yao, J M. Tour
Photoemission spectra have been used to determine the energy-level alignment and work function of monolayers of 4,4'-bis-(phenylethynyl)benzenethiol, 2 naphthalene thiol, and 3-(naphthalen-2-yl)propane-1-thiol self-assembled on Ag, Cu, Au, and Pt. For each
The interactions between cholesterol and saturated phospholipids in hybrid bilayer membranes (HBMs) were investigated using the interface-sensitive technique of vibrational sum frequency spectroscopy (VSFS). The unique sensitivity of VSFS to order/disorder
Tung T. To, Charles Duke, T J. Burkey, Edwin J. Heilweil
The chelation dynamics of three new [Cr{?6-C6H5C(O)R}(CO)3] complexes 1 (R = CH2(SCH3)), 2 (R = CH(SCH3)2), and 3 (R = C(SCH3)3) in room temperature heptane, THF, and acetonitrile solutions have been investigated on the picosecond to millisecond timescale
Neil A. Anderson, Lee J. Richter, John C. Stephenson, Kimberly A. Briggman
The main gel-to-liquid-crystal (LC) phase transition temperature, Tm, of the distal lipid layer in hybrid bilayer membranes (HBMs) under water was investigated using vibrational sum frequency spectroscopy (VSFS). VSFS has unique sensitivity to order
We probed four closely spaced rovibrational water vapor absorption transitions near wavenumber = 7100 cm(^-1) using frequency-stabilized cavity ring-down spectroscopy. Room-temperature spectra were acquired for pure water vapor in the Doppler limit and for
James E. Maslar, Wilbur S. Hurst, Donald R. Burgess Jr., William A. Kimes, Nhan V. Nguyen
In this work, the species present in the gas phase during atomic layer deposition of hafnium oxide were investigated in an attempt to gain insight into the chemistry of this system. Hafnium oxide was deposited on a silicon substrate using tetrakis