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https://www.nist.gov/people/jon-r-pratt
Jon R. Pratt (Fed)
Dr. Pratt is a mechanical engineer and Chief of the Quantum Measurement Division of the Physical Measurement Laboratory (PML) at the National Institute of Standards and Technology (NIST).
Jon R. Pratt, Stephan Schlamminger, Dalziel Wilson, Charles Condos, Aman Rajendra Agrawal, Christian Pluchar
We derive a nonlinear equation of motion for a chip-scale pendulum comprising a thick plate suspended from a tensioned nanoribbon. Recently we explored the use
Jon R. Pratt, Stephan Schlamminger, Charles Condos, Jack Manley, Dalziel Wilson
We previously reported the use of a chip-scale torsion pendulum as a clock gravimeter, exploiting the parametric coupling of its frequency to the local
Vincent Lee, Stephan Schlamminger, Leon Chao, David B. Newell, Jon Pratt, Craig Shakarji, Clive Speake
This paper discusses the dimensional metrology challenges encountered while performing G measurements using the BIPM torsion balance and our solutions.
Stephan Schlamminger, Leon Chao, Vincent Lee, David B. Newell, Jon Pratt, Clive Speake
Four fundamental forces, or technically more correct interactions, are known in physics. The gravitational force is one of them and is a mysterious one. Gravity
The present invention features a micrometer-scale torsion balance device comprising a rigid mass and two or more nanoribbons attached to the rigid mass. The rigid mass may be suspended by the two or more nanoribbons. The two or more nanoribbons may be placed under tensile stress. A local
An absolute mass balance determines an absolute mass of an object and includes: a dual diameter wheel including: a balance fulcrum; and a balance beam disposed on the balance fulcrum and including: a main mass arm and a counter mass arm; a main mass receiver that receives the object; a main magnet
An optomechanical gravimeter includes: a first and second accelerometer; and a spacer member interposed between the first accelerometer and the second accelerometer such that the first accelerometer and the second accelerometer independently include: a basal member; a test mass disposed on the basal