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Search Publications by: Jon R. Pratt (Fed)

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Displaying 76 - 100 of 209

Accurate Picoscale Forces for Insitu Calibration of AFM

September 3, 2009
Author(s)
Koo-Hyun Chung, Gordon A. Shaw, Jon R. Pratt
The force sensitivity of an atomic force microscope is calibrated directly using an in situ realization of primary electrostatic forces ranging from 320 pN to 3.3 nN with accuracy of a few percent. The absolute accuracy of a common atomic force microscope

Methods for transferring the SI unit of force from millinewtons to piconewtons

June 1, 2009
Author(s)
Gordon A. Shaw, Koo-Hyun Chung, Douglas T. Smith, Jon R. Pratt
The establishment of standards for small force measurement requires a link to an absolute measurement of force traceable to the international system of units (SI). To this end, a host of different means are being employed by the NIST small force

Accurate Picometers for DC and Low-Frequency Displacement Measurement

April 6, 2009
Author(s)
Jon R. Pratt, Douglas T. Smith, Lowell Howard
We have developed a fiber-optic interferometer optimized for best performance in the frequency range from DC to 1 kHz, with displacement linearity of 1 % over a range of 25 nm, and noise-limited resolution of 2 pm [1]. The interferometer uses a tunable

2nd Annual Tri-National Workshop on Standards for Nanotechnology - (NIST presentations)

December 10, 2008
Author(s)
Ronald G. Dixson, Jon R. Pratt, Vincent A. Hackley, James E. Potzick, Richard A. Allen, Ndubuisi G. Orji, Michael T. Postek, Herbert S. Bennett, Theodore V. Vorburger, Jeffrey A. Fagan, Robert L. Watters
A new era of cooperation between North American National Measurement Institutes (NMIs) was ushered by the National Research Council of Canada Institute for National Measurement Standards (NRC-INMS) on February 7, 2007 when the first Tri-National workshop

Comparison of NIST SI Force Scale to NPL SI Mass Scale

October 19, 2008
Author(s)
Christopher W. Jones, John A. Kramar, Stuart Davidson, Richard Leach, Jon R. Pratt
Small masses in the 1.0 mg to 0.1 mg range were developed and calibrated at NPL with traceability to the IPK. These masses were transported to NIST at Gaithersburg and used as deadweights on the NIST electrostatic force balance, to facilitate a mass-force

A New Microdevice for SI-Traceable Forces in Atomic Force Microscopy

June 2, 2008
Author(s)
Gregory W. Vogl, Jason J. Gorman, Gordon A. Shaw, Jon R. Pratt
A new self-excited micro-oscillator is proposed as a velocity standard for dissemination of nanoNewton-level forces that are traceable to the International System of Units (SI). The microfabricated oscillator is top-coated with magnetic thin films and