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NIST Authors in Bold

Displaying 751 - 775 of 853

Progress Toward Corrugated Feed Horn Arrays in Silicon

December 16, 2009
Author(s)
Joseph W. Britton, Ki W. Yoon, James A. Beall, Daniel T. Becker, Hsiao-Mei Cho, Gene C. Hilton, Michael D. Niemack, Kent D. Irwin
We are developing monolithic arrays of corrugated feed horns fabricated in silicon for dual-polarization single mode operation at 90, 145 and 220 GHz. The arrays consist of hundreds of platelet feed horns assembled from gold coated stacks of micromachined

Quasi-phasematched Second Harmonic Generation in GaAs Microdisks

November 15, 2009
Author(s)
Paulina S. Kuo, W Fang, Glenn S. Solomon
We discuss design and tuning of second-harmonic generation in GaAs microdisks. Quasi-phasematching can be achieved in the microdisk geometry without external domain inversions, but efficient nonlinear optical mixing requires that all waves be resonant

Optical frequency stabilization of a 10 GHz Ti:sapphire frequency comb by saturated absorption spectroscopy in 87Rubidium

November 4, 2009
Author(s)
Dirk Heinecke, Albrecht Bartels, Tara M. Fortier, Danielle Braje, Leo Hollberg, Scott A. Diddams
The high power per mode of a recently-developed 10 GHz femtosecond Ti:sapphire frequency comb permits nonlinear Doppler-free saturation spectroscopy in 87Rubidium with a single mode of the comb. We use this access to the natural linewidth of the Rubidium

Preparation of Dicke States in an Ion Chain

November 2, 2009
Author(s)
David Hume, Chin-Wen Chou, Till P. Rosenband, David J. Wineland
We have investigated theoretically and experimentally a method for preparing Dicke states in trapped atomic ions. We consider a linear chain of N ion qubits that is prepared in a particular Fock state of motion, jmi. The m phonons are removed by applying a

Effect of Surface Modes on Photon Propagation through Dielectric Bandgaps

October 28, 2009
Author(s)
Natalia Malkova, Sergey V. Polyakov, Alan L. Migdall, Garnett W. Bryant
We investigate the Hartman saturation effect of photons traveling through barriers created by bandgaps of multilayer stacks. In particular, we investigate theoretically the recently observed jumps in photon transversal times due to adding a single layer

Uncooled, Millimeter-Scale Atomic Magnetometers with Femtotesla Sensitivity

October 26, 2009
Author(s)
John E. Kitching, Svenja A. Knappe, William C. Griffith, Jan Preusser, V Gerginov, Peter D. Schwindt, Vishal Shah, Ricardo Jimenez Martinez
We summarize recent results at NIST to develop high-performance yet highly miniaturized magnetic sensors based on atomic vapors confined in microfabricated alkali vapor cells. These sensors currently achieve sensitivities in the range of a few tens of

Measuring the EUV-induced contamination rates of TiO2-capped multilayer optics by anticipated production-environment hydrocarbons

October 1, 2009
Author(s)
Shannon B. Hill, Nadir S. Faradzhev, Charles S. Tarrio, Thomas B. Lucatorto, Robert A. Bartynski, B. V. Yakshinskiy, T. E. Madey
The primary, publicly reported cause of optic degradation in pre-production extreme-ultraviolet (EUV) lithography systems is carbon deposition. This results when volatile organics adsorb onto optic surfaces and then are cracked by EUV-induced reactions

Relative Photon-to-Carrier Efficiencies of Alternating Nanolayers of Zinc Phthalocyanine and C60 Multilayer Films Assessed by Time-Resolved Terahertz Spectroscopy

October 1, 2009
Author(s)
Okan Esenturk, Joseph S. Melinger, Paul A. Lane, Edwin J. Heilweil
Alternating multi-layer and 1:1 blended films of zinc phthalocyanine (ZnPc)and buckminsterfullerene (C60) were investigated as model active layers for solar cells by Time-Resolved Terahertz Spectroscopy (TRTS). Relative photon-to-carrier efficiencies 2

Generation and Mixing of Subfemtoliter Aqueous Droplets on Demand

August 27, 2009
Author(s)
Kristian Helmerson, Jianyong N. Tang, Ana Jofre, Rani Kishore, Joseph E. Reiner, Mark E. Greene, Geoffrey M. Lowman, John Denker, Christina N. Willis, Lori Goldner
We describe a novel method of generating monodisperse sub-femtoliter aqueous droplets on demand by means of piezoelectric injection. Droplets with volumes down to 200 aL are generated by this technique. The droplets are injected into a low refractive index

The Extension of the NIST BRDF Scale from 1100 nm to 2500 nm

August 21, 2009
Author(s)
Howard W. Yoon, David W. Allen, George P. Eppeldauer, Benjamin K. Tsai
Measurements of bi-directional reflectance factor for diffuse reflectance from 1100 nm to 2500 nm using extended-range indium gallium arsenide (exInGaAs) detectors in the NIST Spectral Tri-function Automated Reference Reflectometer (STARR) facility are

Coalescing GSICS Correction Coefficients

August 14, 2009
Author(s)
Ruediger Kessel
We would like to present a technique to adjust the uncertainty estimates of each point in a time series, so that the variance of the time series is consistent with the uncertainty estimates of its component points. This would allow the uncertainty of the

Developing an Uncertainty Analysis for Optical Scatterometry

August 3, 2009
Author(s)
Thomas A. Germer, Heather J. Patrick, Richard M. Silver, Benjamin Bunday
This article describes how an uncertainty analysis may be performed on a scatterometry measurement. A method is outlined for propagating uncertainties through a least-squares regression. The method includes the propagation of the measurement noise as well

Tracking down sources of carbon contamination in EUVL exposure tools

August 3, 2009
Author(s)
Charles S. Tarrio, Robert E. Vest, Thomas B. Lucatorto, R. Caudillo
Optics in EUVL exposure tools are known to suffer reflectivity degradation, mostly from the buildup of carbon. The sources of this carbon have been difficult to identify. Vacuum cleanliness is normally monitored with a residual gas analyzer, but this has

Coherent linear optical sampling at over 15 bits of resolution

July 15, 2009
Author(s)
Ian R. Coddington, William C. Swann, Nathan R. Newbury
Linear optical sampling characterizes a sample by measuring the distortions on a transmitted optical field, thereby quantifying the sample's optical response. By exploiting the high mutual coherence between two phase-locked femtosecond fiber lasers, we

Intensity dynamics in semiconductor laser arrays

July 13, 2009
Author(s)
Kevin L. Silverman, Mingming M. Feng, Richard P. Mirin, Steven T. Cundiff, Matt Williams, J. Nathan N. Kutz
The dynamics of a five-emitter semiconductor laser array is studied theoretically with steady-state, oscillatory, and chaotic behaviors achieved. This provides a design tool for achieving oscillations whose frequency is related to injection current.

Using the nonlinear Schroedinger equation for precision optical measurements

July 6, 2009
Author(s)
Nathan R. Newbury, Esther Baumann, Ian R. Coddington, Fabrizio R. Giorgetta, William C. Swann
Frequency combs produce light that is both broadband and highly coherent. However, their operation relies on the nonlinear Schroedinger equation, in particular to achieve the broad spectral output. Because it is a highly nonlinear system, this comb output

Supercontinuum Sources for Metrology

June 2, 2009
Author(s)
John T. Woodward IV, Allan W. Smith, Colleen A. Jenkins, Chungsan Lin, Steven W. Brown, Keith R. Lykke
Supercontinuum (SC) sources are novel laser-based sources that generate a broad, white-light continuum in single mode photonic crystal fibers. Currently, up to 6 W of optical power is available, spanning the spectral range from 460 nm to 2500 nm. Advances

Intensity dynamics in a waveguide array laser

May 31, 2009
Author(s)
Mingming M. Feng, Steven T. Cundiff, Kevin L. Silverman, Richard Mirin, Matt Williams, J. Nathan N. Kutz
We report the intensity dynamics of a five-emitter laser array subject to a linearly decreasing injection current. The array produces oscillatory power output with a nearly Pi phase shift between the oscillations of adjacent waveguides.

Time and Frequency-Domain Spectroscopy with Dual Frequency Combs

May 28, 2009
Author(s)
Nathan R. Newbury, Ian R. Coddington, William C. Swann
High-resolution spectroscopic measurements of the amplitude and phase spectra from a gas sample can be acquired by use of dual frequency combs. Here we discuss the corresponding gas signature in the time domain.

A deep-UV optical frequency comb at 205 nm

May 25, 2009
Author(s)
Scott A. Diddams, E Peters, P Fendel, S Reinhardt, T W. Hansch, T Udem
By frequency quadrupling a picosecond pulse train from a Ti:sapphire laser at 820 nm we generate a frequency comb at 205 nm with nearly bandwidth-limited pulses. The nonlinear frequency conversion is accomplished by two successive frequency doubling stages

Imaging Response of Optical Microscopes Containing Angled Micromirrors

April 30, 2009
Author(s)
Andrew J. Berglund, Matthew D. McMahon, Jabez J. McClelland, James A. Liddle
We describe the aberrations induced by introducing micromirrors into the object space of a microscope. These play a critical role in determining the accuracy of recent three-dimensional particle tracking methods based on such devices.

Frequency comb spectroscopy with coherent optical sampling

April 20, 2009
Author(s)
Ian R. Coddington, Nathan R. Newbury, William C. Swann
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.
Displaying 751 - 775 of 853
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