High-Q resonant sensors enable ultra-sensitive force and field detection. In this talk I will describe two applications of these sensors in searches for new physics. In high vacuum, optically levitated dielectric microspheres achieve excellent decoupling from their environment and experience minimal friction. Hence they can be used for sensitive force measurements. We have shown that such beads can be stably trapped under high vacuum conditions for long time periods and can be used for attonewton force measurements in a dual beam optical trap. I will describe our progress towards using these sensors for tests of the Newtonian gravitational inverse square law at micron length scales. Next I will describe a new method based on nuclear magnetic resonance which can detect short-range spin-dependent forces from axion-like particles. The method can potentially improve previous experimental bounds by several orders of magnitude and can probe deep into the theoretically interesting regime for the QCD axion.

A.Geraci, S. Papp, and J. Kitching, Phys. Rev. Lett. 105, 101101 (2010)
G. Ranjit, D. P. Atherton, J. H. Stutz, M. Cunningham, and A. A. Geraci, Phys. Rev. A 91, 051805(R) (2015)
A. Arvanitaki and A. Geraci, Phys. Rev. Lett. 113, 161801 (2014).

Argonne Physics Division Colloquium Schedule