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John Unguris
No full textJOHN UNGURIS
NBS/NIST: 1980–2018
INDUCTED: 2022
Birth: 1950, Diez, Germany
EDUCATION:
Carnegie Mellon University, BS (Physics), 1973
University of Wisconsin, Madison, PhD (Physics), 1980
CITATION: For pioneering the development of Scanning Electron Microscopy with Polarization Analysis (SEMPA) and its use for direct, high spatial resolution, quantitative imaging of magnetic nanostructures for both science and industry
POSITIONS HELD AT NBS/NIST:
NAS/NRC Postdoctoral Research Associate, Radiation Physics Division, National Measurement Laboratory (NML), 1980-1982
Physicist/Project Leader, Electron Physics Group, Electron and Optical Physics Division, NML/Physics Laboratory, 1982-2007
Physicist, Electron Physics Group, Center for Nanoscale Science and Technology, 2007-2018
Guest Researcher, Nanoscale Device Characterization Division, Physical Measurement Laboratory, 2018-
HONORS:
NIST Bronze Medal (1989)
Sigma Xi Young Scientist Award (1990)
Fellow, American Physical Society (1996)
Joseph F. Keithley Award, American Physical Society (2015)
MEMBERSHIPS:
American Physical Society
American Vacuum Society
Microscopy Society of America
PUBLICATIONS:
More than 105 publications and one patent including:
Unguris, J., Seiler, A., Celotta, R.J., Pierce, D.T., Johnson, P.D., and Smith, N.V., “Spin-Polarized Inverse Photoelectron Spectroscopy of Solid Surfaces: Ni(110)”, Physical Review Letters 49, 1047-1050 (1982)
Pierce, D.T., Celotta, R.J., and Unguris, J., Apparatus and Method for Electron Spin Polarization Detection, US Patent 4,760,254 (July 26, 1988)
Scheinfein, M.R., Unguris, J., Kelly, M.H., Pierce, D.T., and Celotta, R.J., “Scanning Electron Microscopy with Polarization Analysis (SEMPA)”, Review of Scientific Instruments 61, 2501-2527 (1990)
Unguris, J., Celotta, R.J., and Pierce, D.T., “Observation of Two Different Oscillation Periods in the Exchange Coupling of Fe/Cr/Fe(100)”, Physical Review Letters 67, 140-143 (1991)
Unguris, J., Celotta, R.J., and Pierce, D.T., “Magnetism in Cr Thin Films on Fe(100)”, Physical Review Letters 69, 1125-1128 (1992)
McMorran, B.J., Agrawal, A., Anderson, I.M., Herzing, A.A., Lezec, H.J., McClelland, J.J., and Unguris, J., “Electron Vortex Beams with High Quanta of Orbital Angular Momentum”, Science 331, 192-195 (2011
James A. Beall
No full textJAMES A. BEALL
NBS/NIST: 1982–2021
INDUCTED: 2022
Birth: 1954, Cumberland, Maryland
EDUCATION:
Brown University, BA (Mathematics), 1976
University of Colorado, Boulder, MS (Electrical Engineering), (1983)
CITATION: For creating microfabrication capabilities that enabled a wide range of groundbreaking research, and for developing best-in-the-world superconducting devices including sensors for astrophysics and materials analysis
POSITIONS HELD AT NBS/NIST:
Electronics Engineer, Cryoelectronic Metrology Group, Electromagnetic Technology Division, National Engineering Laboratory/Electronics and Electrical Engineering Laboratory (EEEL) (Boulder), 1982-2010
Electronics Engineer, Quantum Devices Group, Quantum Electrical Metrology Division, Physical Measurement Laboratory (PML) (Boulder), 2010-2021
Guest Researcher, Quantum Sensors Group, Quantum Electromagnetics Division, PML (Boulder), 2021-
HONORS:
U.S. Department of Commerce Gold Medals (1989, 1993, 2012, and 2021)
NIST Bronze Medals (2004 and 2017)
NIST Colleagues’ Choice Award (2012)
MEMBERSHIPS:
Phi Beta Kappa
PUBLICATIONS:
More than 210 publications including:
Zimmerman, J.E., Beall, J.A., Cromar, M.W., and Ono, R.H., “Operation of a Y‐Ba‐Cu‐O rf SQUID at 81 K”, Appl. Phys. Lett. 51, 617-618 (1987)
Lloyd, F.L., Hamilton, C.A., Beall, J.A., Go, D., Ono, R.H., and Harris, R.E., “A Josephson Array Voltage Standard at 10 V”, IEEE Electron Device Lett. 8, 449-450 (1987)
Rowe, M.A., Ben-Kish, A., DeMarco, B., Leibfried, D., Meyer, V., Beall, J., Britton, J., Hughes, J., Itano, W.M., Jelenkovic, B., Langer, C., Rosenband, T., and Wineland, D.J., “Transport of Quantum States and Separation of Ions in a Dual RF Ion Trap”, Quantum Inf. Comput. 2, 257-271 (2002)
Rafac, R.J., Young, B.C., Beall, J.A., Itano, W.M., Wineland, D.J., and Bergquist, J.C., “Sub-dekahertz Ultraviolet Spectroscopy of 199Hg+”, Phys. Rev. Lett. 85, 2462-2465 (2000)
Hanson, D., Hoover, S., Crites, A., Ade, P.A.R., Aird, K.A., Austermann, J.E., Beall, J.A., et al., “Detection of B-Mode Polarization in the Cosmic Microwave Background with Data from the South Pole Telescope”, Phys. Rev. Lett. 111, 141301 (2013)
Henderson, S.W., Allison, R., Austermann, J., Baildon, T., Battaglia, N., Beall, J.A., et al., “Advanced ACTPol Cryogenic Detector Arrays and Readout”, J. Low Temp. Phys. 184, 772-779 (2016
Feasibility of Modeling Orthogonal Frequency-Division Multiplexing Communication Signals with Unsupervised Generative Adversarial Networks
No full textHigh-quality recordings of radio frequency (RF) emissions from commercial communication hardware in realistic environments are often needed to develop and assess spectrum-sharing technologies and practices, e.g., for training and testing spectrum sensing algorithms and for interference testing. Unfortunately, the time-consuming, expensive nature of such data collections together with data-sharing restrictions pose significant challenges that limit data set availability. Furthermore, developing accurate models of real-world RF emissions from first principles is often very difficult because system parameters and implementation details are at best only partially known, and complex system dynamics are difficult to characterize. Hence, there is a need for flexible, data-driven methods that can leverage existing data sets to synthesize additional similar waveforms. One promising machine-learning approach is unsupervised deep generative modeling with generative adversarial networks (GANs). To date, GANs for RF communication signals have not been studied thoroughly. In this paper, we present the first in-depth investigation of generated signal fidelity for GANs trained with baseband orthogonal frequency-division multiplexing (OFDM) signals, where each subcarrier is digitally modulated with quadrature amplitude modulation (QAM). Building on prior GAN methods, we developed two novel GAN models and evaluated their performance using simulated data sets with known ground truth. Specifically, we investigated model performance with respect to increasing data set complexity over a range of OFDM parameters and conditions, including fading channels. The findings presented here inform the feasibility of use cases and provide a foundation for further investigations into deep generative models for RF communication signals
The NIST Vacuum Double-Crystal Spectrometer: A Tool for SI-Traceable Measurement of X-Ray Emission Spectra
No full text
Porosity, Powder X-Ray Diffraction Patterns, Skeletal Density, and Thermal Stability of NIST Zeolitic Reference Materials RM 8850, RM 8851, and RM 8852
No full textThis paper reports the powder X-ray diffraction patterns, argon isotherms at 87 K, Brunauer–Emmett–Teller surface areas, pore size distributions, pore volumes, skeletal densities, and thermal gravimetric analyses for three National Institute of Standards and Technology zeolitic reference materials, RM 8850 (zeolite Y), RM 8851 (zeolite A), and RM 8852 (ZSM-5
Acceptance Testing Methodology for the Production of Standard Reference Material 2806: Medium Test Dust in Hydraulic Fluid
No full textStandard Reference Material (SRM) 2806: Medium Test Dust in Hydraulic Fluid represents a series of reference materials certified by the National Institute of Standards and Technology (NIST) used to calibrate liquid-borne optical (or automatic) particle counters applied in a wide range of industrial, aerospace, and military applications. The series, including SRM 2806b, and SRM 2806d, was manufactured for NIST by IFTS, Institut de la Filtration et des Techniques Séparatives International Filter Testing Services, in France. An important factor for the acceptance of the material for certification was the degree of bottle-to-bottle homogeneity, which was evaluated by both IFTS and NIST. A statistical graphics methodology was developed that provided immediate visual as well as quantitative statistical metrics with which to characterize the SRM. This NIST-developed approach was used in four studies to assess the homogeneity of the material during both its production stage and its finished bottled-product stage. IFTS performed measurements using an optical particle counter for on-line quality assurance and sampled 40 bottles of the finished 400 bottle series to determine homogeneity from the particle size distribution. NIST also determined the particle size distribution of the finished material and performed microscopy to look for possible contaminant material in the suspension. An accelerated aging experiment was conducted on both materials (2806b and 2806d) to verify their stability
Geoffrey B. McFadden
No full textGEOFFREY B. MCFADDEN
NBS/NIST: 1982–2021
INDUCTED: 2022
Birth: 1953, Stillwater, Minnesota
EDUCATION:
Rice University, BA (Chemical Physics, Mathematical Sciences, Mathematics), 1975
New York University, MS (Mathematics), 1977
New York University, PhD (Mathematics), 1979
CITATION: For groundbreaking contributions to the theory of phase transitions, hydrodynamic and morphological stability, and thermosolutal transport in materials, resulting in powerful predictive tools for materials science
POSITIONS HELD AT NBS/NIST:
Mathematician, Mathematical Analysis Division, Center for Applied Mathematics, National Engineering Laboratory/Computing and Applied Mathematics Laboratory/Information Technology Laboratory (ITL), 1982-1999
Leader, Mathematical Modeling Group, Mathematical and Computational Sciences Division, ITL, 1999-2010
NIST Fellow, Mathematical and Computational Sciences Division/Applied and Computational Mathematics Division, ITL, 2004-2021
HONORS:
U.S. Department of Commerce Silver Medal (1984)
Arthur S. Flemming Award for Federal Service (1989)
U.S. Department of Commerce Gold Medal (1991)
Fellow, American Physical Society (2001)
Fellow, Washington Academy of Sciences (2012)
Fellow, Society for Industrial and Applied Mathematics (2012)
MEMBERSHIPS:
American Physical Society
Washington Academy of Sciences
Society for Industrial and Applied Mathematics
PUBLICATIONS:
More than 215 publications including:
Coriell, S.R., McFadden, G.B., and Sekerka, R.F., “Cellular Growth During Directional Solidification”, Annual Review of Materials Science 15, 119-145 (1985)
Glicksman, M.E., Coriell, S.R., and McFadden, G.B., “Interaction of Flows with the Crystal-Melt Interface”, Annual Review of Fluid Mechanics 18, 307-335 (1986)
Wheeler, A.A., Boettinger, W.J., and McFadden, G.B., “A Phase-Field Model for Isothermal Phase Transitions in Binary Alloys”, Physical Review A 45, 7424-7439 (1992)
McFadden, G.B., Wheeler, A.A., Braun, R.J., Coriell, S.R., and Sekerka. R.F., “Phase-Field Models for Anisotropic Interfaces”, Physical Review E 48, 2016-2024 (1993)
Anderson, D.M., McFadden, G.B., and Wheeler, A.A., “Diffuse-Interface Methods in Fluid Mechanics”, Annual Review of Fluid Mechanics 30, 139-165 (1998)
Sekerka, R.F., Coriell, S.R., and McFadden, G.B., “Morphological Stability”, Handbook of Crystal Growth, Vol. I, 2nd Edition, 595-630 (2015
