Levitated optomechanical systems, also known as optical tweezers, have proven to be excellent platforms for high-precision sensing and studies of mesoscopic physics. Experimentally observed mechanical oscillator quality factors of over a billion are evidence of the extremely low noise and damping that allows these systems to approach the standard quantum limit. Researchers, including at AFRL, have demonstrated the ability to resolve optically trapped nanoparticle oscillations as small as 100 femtometers and oscillating forces as small as a zeptoNewton in only one second of data acquisition, which supports our current efforts to develop high-precision inertial and electric field sensors. Optically levitated nanoparticles around 100 nanometers in size have also been placed in the quantum harmonic oscillator ground state of various degrees of freedom, sometimes simultaneously. For this reason, it may be possible to place these relatively-large particles in quantum superpositions to test theories that seek to unify quantum and classical mechanics and understand the quantum or non-quantum nature of gravity as well as sense inertial, gravitational, and electromagnetic forces with unprecedented precision. At AFRL, we also actively collaborate with university researchers to explore optical refrigeration of novel materials in levitated systems and understand how cooling optically levitated particles might benefit sensing and mesoscopic physics experiments.

Our research focuses on experimental investigations but includes theory as well. Experimental efforts involve working with optics, lasers, vacuum equipment, and custom electronics as well as programming.

Millen, J., Monteiro, T. S., Pettit, R., Vamivakas, N. A. “Optomechanics with levitated particles.” Rep. Prog. Phys. 83, 026401 (2020).

Tebbenjohanns, F., Mattana, M.L., Rossi, M., Frimmer, M., Novotny, L. “Quantum control of a nanoparticle optically levitated in cryogenic free space.” Nature 595, 378–382 (2021).

key words

levitated; optomechanics; nanoparticles; optical tweezers; optical refrigeration; laser cooling; sensing; precision; interferometry

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral and Senior applicants