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PhD Candidate Name: Charles Blakemore


Research Advisor: Giorgio Gratta


Date:  Tuesday, August, 17, 2021

Time:  3:00pm PDT

Zoom Link:

Zoom Password:  email


Title:  Fundamental and Applied Physics with Optically Levitated Microspheres


Abstract:   The field of optomechanics, which leverages interactions between optical fields and sub-millimeter-sized objects, has allowed the realization of a number of scientific advancements ranging from manipulation of biological systems to the implementation of quantum simulators. In this talk, I will discuss a series of technical developments using optically levitated silica microspheres, as well as the application of these techniques toward investigations of fundamental physics. Some of the technical advancements made with this apparatus include single-beam trapping with interferometric imaging, three-dimensional force-field microscopy, electrically driven rotation, in situ mass measurements of levitated particles, as well as the realization of a spinning rotor vacuum gauge. Using the microsphere as a force sensor, in concert with some of the aforementioned techniques, we have performed a search for screened interactions that could be associated with dark energy, as well as a search for short-distance modifications to the classical Newtonian gravitational potential. The latter topic, while intrinsically interesting, may also shed light on beyond the Standard Model theories.


August 17, 2021 - 3:00pm