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Nathan R. Newbury, Ian R. Coddington, Esther Baumann, Fabrizio R. Giorgetta, William C. Swann, Alexander M. Zolot
Fiber-based frequency combs can provide broadband coherent light that enables new possibilities for high-accuracy, high-resolution broadband spectroscopy. We use a configuration with two coherently phase-locked combs; the output of one comb passes through
We present the correlation of the electronic properties at the semiconductor-molecule interface with the nature of the covalent attachment. The chemical state, monolayer structure, and electronic properties of aliphatic monolayers with Si-O, Si-C, and Si-S
Esther Baumann, Fabrizio R. Giorgetta, Ian R. Coddington, William C. Swann, Nathan R. Newbury
A coherent dual fiber-comb spectrometer centered at 1.5 µm wavelengths is transferred to 3.4 µm by difference-frequency generation with a 1064 nm cw laser. It is shown that the residual linewidth between the comb teeth at 3.4 µm is resolution-limited to
Charles W. Clark, Ennio Arimondo, William C. Martin
In the early days of theoretical atomic spectroscopy, Ettore Majorana (1906-1938?) solved several outstanding problems by developing the theory of autoionization. Later literature makes only sporadic references to this accomplishment. Reviewing his work in
Keith A. Gillis, Daniel K. Havey, Joseph T. Hodges
We model and measure the absolute response of an intensity-modulated photoacoustic spectrometer comprising a 10 cm long resonator and having a Q-factor of approximately 30. We present a detailed theoretical analysis of the system and predict its response
Brent A. Sperling, William A. Kimes, James E. Maslar, Pamela M. Chu
In this work, we develop a Fourier transform infrared spectroscopy-based method to measure the gas-phase dynamics occurring during atomic layer deposition of hafnium oxide using tetrakis (ethylmethylamido) hafnium and water vapor. We take advantage of the
Yvonne B. Gerbig, Stephan J. Stranick, Robert F. Cook
The residual stress field around spherical indentations on single crystal silicon (Si) of different crystallographic orientation is mapped by confocal Raman microscopy. All orientations exhibit an anisotropic stress pattern with an orientation specific
Chin J. Chiang, Thomas M. Wallis, Dazhen Gu, Atif A. Imtiaz, Pavel Kabos, Paul T. Blanchard, Kristine A. Bertness, Norman A. Sanford, Kichul Kim, Dejan Filipovic
A GaN nanowire (NW) Schottky contact was characterized up to 10 GHz. Using a calibration procedure and circuit model a capacitance-voltage (CV) curve was obtained, from which a carrier concentration was calculated for the first time. These results
Fabrizio R. Giorgetta, Ian R. Coddington, Esther Baumann, William C. Swann, Nathan R. Newbury
Frequency combs provide broadband spectroscopic measurements with high frequency accuracy and precision. However, because the comb power is distributed over a broad spectrum, the sensitivity can be low unless some form of multiplexed detection or cavity
For more than 50 years, Charlotte Moore's Atomic Energy Levels compilation and its subsequent revisions have been the standard source of reference data for the spectra of hydrogen and its isotopes. In these compilations, theoretical data based on quantum
David R. Black, Donald A. Windover, Albert Henins, David L. Gil, James J. Filliben, James P. Cline
The National Institute of Standards and Technology (NIST) certify a variety of standard reference materials (SRM) to address specific aspects of instrument performance for divergent beam diffractometers. This report describes SRM 640d, the fifth generation
Brent A. Sperling, William A. Kimes, James E. Maslar
Tetrakis(ethylmethylamido)hafnium and water are commonly used precursors for atomic layer deposition of HfO2. Using reflection absorption infrared spectroscopy with a buried-metal-layer substrate, we probe surface species present during typical deposition
Eduard Rocas, Juan C. Collado Gomez, Nathan D. Orloff, James C. Booth
We present measurements and modeling of a self-heating mechanism responsible for third order intermodulation distortion in coplanar waveguide transmission lines. Temperature fluctuations, at the envelope frequency of the input signal, induce dynamic
James E. Maslar, Ramon Cusco, Esther Alarcon-Llado, Luis Artus, Wilbur S. Hurst
We present a detailed investigation of the phonons and LO-phononplasmon coupled modes in the Ga1−x InxAsy Sb1−y alloy by means of Raman scattering. A generalization of the dielectric Raman lineshape model to quaternary alloys is described and used to
Fabrizio R. Giorgetta, Ian R. Coddington, William C. Swann, Esther Baumann, Nathan R. Newbury
Dual, coherent frequency combs are used to measure the spectrum of an incoherent, quasi-thermal source through Fourier spectroscopy. The source spectrum is acquired over 1THz bandwidth with an absolute frequency accuracy set by the combs.
Christina A. Hacker, Mariona Coll Bau, Curt A. Richter
Scaling of conventional electronics has continued unabated to dimensions approaching fundamental physical limits. As technology continues to evolve there are increasing demands to identify alternate routes of performing electrical functions. One potential
Vladimir L. Orkin, Larissa E. Martynova, Alexander N. Ilichev
Rate constants for the gas phase reactions of OH radicals with two isomers of tetrafluoropropene, CH2=CF-CF3 (k1) and trans-CHF=CH-CF3 (k2); were measured using a flash photolysis resonance-fluorescence technique over the temperature range 220 K to 370 K
Okan Esenturk, Joseph S. Melinger, Paul A. Lane, Edwin J. Heilweil
Intrinsic properties of organic semiconductors are investigated by Time-Resolved Terahertz Spectroscopy (TRTS) to assess their relative mobilities and efficiencies. Our results are well correlated with device measurements, and show the effectiveness and
David P. Pappas, Jeffrey S. Kline, Willim R. Kelley, Zachary Dutton, Thomas A. Ohki, john Schlafer, Bashkar Mookerji
The phenomenon of coherent population trapping (CPT) of an atom (or solid state artificial atom ), and the associated effect of electromagnetically induced transparency (EIT), are clear demonstrations of quantum interference due to coherence in multilevel
NO3 has been stabilized in a neon matrix at 4.3 K in sufficient yield for detection of the absorptions between 7000 and 10000 cm-1 which arise from vibronically allowed transitions from its ground state to levels of the A 2E" state. The results confirm and
Jason Hattrick-Simpers, Chun Chiu, James E. Maslar, Leonid A. Bendersky, Michael E. Niemann, Sesha S. Srinivasan, Elias K. Stefanakos
In situ Raman spectroscopy was used to monitor the dehydrogenation of ball-milled mixtures of LiNH2 LiBH4 MgH2 nanoparticles. The as-milled powders were found to contain a mixture of Li4BN3H10 and Mg(NH2)2, with no evidence of residual LiNH2 or LiBH4. It