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John A. Kramar

Group Leader

Dr. John Kramar is the Leader of the Nanoscale and Nanostructure Metrology Group in the Microsystems and Nanotechnology Division of the Physical Measurement Laboratory (PML) at the National Institute of Standards and Technology (NIST). He received a B.S. in Chemistry from Abilene Christian University and a Ph.D. in Chemistry from the California Institute of Technology, where he studied the morphology and electronic structure of molybdenum disulfide using scanning tunneling microscopy and spectroscopy. John joined the NIST staff through a National Research Council Postdoctoral Research Associateship award. At NIST, he joined and later led the Molecular Measuring Machine project, for realizing the meter and measuring artifacts with atomic resolution and accuracy over tens-of-millimeters of length. John was also a key member of the NIST electrostatic force balance project for realizing the unit of mass at the milligram level. His current research interests include nanoparticle size and distribution standard reference measurements and the development of instrumentation for precision length metrology at both meter- and micrometer-scale distances. John has been the recipient of four Department of Commerce Medal awards for his research accomplishments: one Bronze, two Silver and one Gold.


Milligram mass metrology using an electrostatic force balance

Gordon A. Shaw, Julian Stirling, John A. Kramar, Alexander D. Moses, Patrick J. Abbott, Richard L. Steiner, Andrew D. Koffman, Jon R. Pratt, Zeina J. Kubarych
Although mass is typically defined within the International System of Units (SI) at the Kilogram level, the pending redefinition of the SI provides an
Created June 18, 2019, Updated May 11, 2020