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Charles W. Clark, official portrait, National Institute of Standards and Technology. Work of U.S. Government not subject to copyright.

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Recent News

  • An artist's depiction of an atom sitting on a representation of a warped spacetime

    The Secrets Atoms Hold, Part 2: Gravity

    May 19, 2021

    In this episode of Relatively Certain, JQI Adjunct Fellow Marianna Safronova and JQI Fellow Charles Clark return to discuss the limits of our understanding of gravity, and how new experiments with atom interferometers may be the key to not only a higher-precision understanding of gravity but also possible new physics.

  • An artists's rendering of an atom with galaxies embedded inside

    The Secrets Atoms Hold, Part 1: Search for Dark Matter

    September 25, 2020

    In this episode of Relatively Certain, Dina Genkina sits down with JQI Adjunct Fellow Marianna Safronova, a physics professor at the University of Delaware, and JQI Fellow Charles Clark, an adjunct professor of physics at UMD and a fellow of the National Institute of Standards and Technology, to talk about how precision measurements with atoms might shed some light on matter that’s otherwise dark.

  • A Twist and a Spin

    November 14, 2019

    By cleverly manipulating two properties of a neutron beam, scientists at the National Institute of Standards and Technology (NIST) and their collaborators have created a powerful probe of materials that have complex and twisted magnetic structures.Penetrating deep inside heavyweight materials, yet still able to interact strongly with light elements, neutron beams image hydrogen-bearing liquids in engine parts, storage tanks and fuel cells. The beams can also map the shapes of polymers on the molecular scale, reveal the precise arrangement of atoms in a crystal and chart the distribution of water within growing plants. Neutron beams became even stronger probes when scientists learned how to harness two quantum properties of the beams. One of these properties, formally known as orbital angular momentum, or OAM, refers to the twisting, or rotational motion of a neutron as it travels forward, similar to the whirlpool formed by water as it travels down a drain. The other quantum property, spin, is related to the neutron’s magnetic field, and can be likened to the spinning motion of a top.

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