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Quantitative Synthetic Polymer Mass Spectrometry Workshop. Gaithersburg, Md. November 7-8, 2002
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Charles W. Clark
No full textCHARLES W. CLARK
NBS/NIST: 1981–1983 and 1984–2022
INDUCTED: 2023
B: 1952, Minneapolis, Minnesota
EDUCATION:
Western Washington State College, BA (Mathematics and Physics), 1974
University of Chicago, SM (Physics), 1976
University of Chicago, PhD (Physics), 1979
CITATION: For providing the theoretical basis for understanding many of the most important aspects of modern atomic, molecular, and optical physics, especially ultracold atoms, Bose-Einstein condensates, and quantum technology
POSITIONS HELD AT NBS/NIST:
NAS/NRC Postdoctoral Research Associate, Atomic and Plasma Radiation Division, Center for Radiation Research (CRR), National Measurement Laboratory (NML), 1981-1983
Physicist, Radiation Physics Division, CRR, NML, 1984-1989
Chief, Electron and Optical Physics Division, Physics Laboratory, 1990-2010
Program Manager, Atomic, Molecular and Quantum Physics, Office of Naval Research, United States Navy (part-time detail 2003-2014)
NIST Fellow, Quantum Measurement Division, Physical Measurement Laboratory, 2010-2022
NIST Co-Director of the Joint Quantum Institute (Joint with University of MD), 2011-2016
HONORS:
Visiting Fellow, Australian National University (1986 and 1992); Dr. Lee Visiting Fellow, Christ Church, University of Oxford (1999); Visiting Scholar, National University of Singapore (2007-2023); Distinguished Visiting Professor of Quantum Physics, University of Malaya (2013-2015); Visiting Scholar, Merton College, University of Oxford (2017-2023)
Excellence in Research Award, NBS Chapter of Sigma Xi (1987)
NIST Equal Employment Opportunity Award (1991); Safety Award (2002); Edward Uhler Condon Award (2002 and 2013)
Fellow: American Physical Society (1992); Optical Society of America (1994); Institute of Physics (UK) (1999); American Association for the Advancement of Science (2001); Washington Academy of Sciences (and Physical Sciences Award) (2003); Joint Quantum Institute (2007-2023)
U.S. Department of Commerce Silver Medal (1994); Gold Medals (2004 and 2011); NIST Bronze Medal (2009)
Archie Mahan Prize, Optical Society of America (2002)
Distinguished Presidential Rank Award (2007)
R&D 100 Award, R&D Magazine (2008)
Award for Information Technology Achievement, Government Computer News (2011)
Honorary Fellow, Bangladesh Physical Society (2021)
MEMBERSHIPS:
American Association for the Advancement of Science, American Physical Society, Bangladesh Physical Society, Cosmos Club, National Society of Black Physicists, Optica
PUBLICATIONS:
Four patents and 250 publications, including:
Olver, F.W.J., Lozier, D.W., Boisvert, R.F., and Clark, C.W., (Eds.), NIST Handbook of Mathematical Functions, Cambridge University Press (2010
(Audio Part 1 of 4) Oral history interview of John Hoffman, May 23, 2003
No full textDr. John Hoffman discusses his long career at NIST. His career spanned the years 1954 to 1982, during which time he was in various leadership positions, including Director of the Institute for Materials Research and Director of the National Measurement laboratory
(Audio Part 2 of 3) Oral history interview of John Hoffman, July 21, 2003
No full textDr. John Hoffman discusses his long career at NIST. His career spanned the years 1954 to 1982, during which time he was in various leadership positions, including Director of the Institute for Materials Research and Director of the National Measurement laboratory
Dependence of electron density on Fermi energy in N-type gallium antimonide
No full textThe majority electron density as a function of the Fermi energy is calculated in zinc blende, n-type GaSb for donor densities between 10(16) cm(-3) and 10(19) cm(-3). These calculations solve the charge neutrality equation self-consistently for a four-band model (three conduction sub-bands at Gamma, L, and X and one equivalent valence band at Gamma) of GaSb. Our calculations assume parabolic densities of states and thus do not treat the density-of-states modifications due to high concentrations of dopants, many body effects, and non-parabolicity of the bands. Even with these assumptions, the results are important for interpreting optical measurements such as Raman measurements that are proposed as a nondestructive method for wafer acceptance tests
Radiometric measurement comparison on the integrating sphere source used to calibrate the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Landsat 7 Enhanced Thematic Mapper Plus (ETM+)
No full textAs part of a continuing effort to validate the radiometric scales assigned to integrating sphere sources used in the calibration of Earth Observing System (EOS) instruments, a radiometric measurement comparison was held in May 1998 at Raytheon/Santa Barbara Remote Sensing (SBRS). This comparison was conducted in support of the calibration of the Moderate Resolution Imaging Spectroradiometer ( MODIS) and the Landsat 7 Enhanced Thematic Mapper Plus (ETM+) instruments. The radiometric scale assigned to the Spherical Integrating Source (SIS100) by SBRS was validated through a comparison with radiometric measurements made by a number of stable, well-characterized transfer radiometers from the National Institute of Standards and Technology (NIST), the National Aeronautics and Space Administration's Goddard Space Flight Center (NASA's GSFC), and the University of Arizona Optical Sciences Center (UA). The measured radiances from the radiometers differed by +/- 3 % in the visible to near infrared when compared to the SBRS calibration of the sphere, and the overall agreement was within the combined uncertainties of the individual measurements. In general, the transfer radiometers gave higher values than the SBRS calibration in the near infrared and lower values in the blue. The measurements of the radiometers differed by +/- 4 % from 800 nm to 1800 nm compared to the SBRS calibration of the sphere, and the overall agreement was within the combined uncertainties of the individual measurements for wavelengths less than 2200 nm. The results of the radiometric measurement comparison presented here supplement the results of previous measurement comparisons on the integrating sphere sources used to calibrate the Multi-angle Imaging SpectroRadiometer (MISR) at NASA's Jet Propulsion Laboratory (JPL), Pasadena, CA and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) at NEC Corporation, Yokohama, Japan
Optical-fiber power meter comparison between NIST and PTB
No full textWe describe the results of a comparison of reference standards between the National Institute of Standards and Technology (NIST-USA) and Physikalisch-Technische Bundesanstalt (PTB-Germany) at nominal wavelengths of 1300 nm and 1550 nm using an optical-fiber cable. Both laboratories used thermal detectors as reference standards. A novel temperature-controlled, optical-trap detector was used as a transfer standard to compare two reference standards. Measurement results showed differences of less than 1.5 x 10(-3), which is within the combined uncertainty for both laboratories
Optical diffraction in close proximity to plane apertures. II. Comparison of half-plane diffraction theories
No full textThe accuracy and physical significance of the classical Rayleigh-Sommerfeld and Kirchhoff diffraction integrals are assessed in the context of Sommerfeld's rigorous theory of half-plane diffraction and Maxwell's equations. It is shown that the Rayleigh-Sommerfeld integrals are in satisfactory agreement with Sommerfeld's theory in most of the positive near zone, except at sub-wavelength distances from the screen. On account of the bidirectional nature of diffraction by metallic screens the Rayleigh-Sommerfeld integrals themselves cannot be used for irradiance calculations, but must first be resolved into their forward and reverse components and it is found that Kirchhoff's integral is the appropriate measure of the forward irradiance. Because of the inadequate boundary conditions assumed in their derivation the Rayleigh-Sommerfeld and Kirchhoff integrals do not correctly describe the flow of energy through the aperture