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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
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
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
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
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
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
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
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
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
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
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
We predict that the optical conductivity of normal graphene multilayers is close to ς uni=(π/2) e 2/h per layer over a broad range of frequencies. The origin of this behavior is an emergent chiral symmetry which is present in normal N-layer stacks when
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
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
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
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.
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
Adriaan C. Carter, Solomon I. Woods, Stephen Carr, Timothy M. Jung, Raju V. Datla
Commercially available Absolute Cryogenic Radiometers (ACRs) have combined uncertainties that grow rapidly above 1% at power levels below 10 nW. There are solid state detectors, however, used in sensors and radiometers that cannot be calibrated at levels
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
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.
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.
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
We experimentally determine the conductivity and optical transmittance of graphite layers, obtained from the liquid phase exfoliation of natural crystalline graphite. The measured transmittance values range from 0.9 to 0.97, comparable to the theoretical
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.
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.