Abstract

The ability to engineer and control the macroscopic motion of nano- and micro-mechanical oscillators has become an important tool in quantum science and technology. Key to the exploitation of these devices has been the development of methods to cool them to their ground state¹. Levitation of a nanomechanical oscillator in vacuum, such as an optically trapped nanosphere, removes many dissipation and decoherence pathways and leads to extremely high mechanical quality factors². This offers great promise for force sensing³, for exploring the foundations of quantum mechanics at large mass scales and the possibility of creating large macroscopic superpositions⁴. In this talk I will introduce levitated cavity optomechanics and focus on the science and potential applications of levitated systems. Finally, I will describe our experiments that have cooled levitated 200 nm silica spheres in vacuum by using a hybrid electro-optical trap.

[1] J. D. Teufel, J. D. et al., Sideband cooling of micromechanical motion to the quantum ground state. Nature 475, 359 (2011) [2] D. E. Chang et al., Cavity opto-mechanics using an optically levitated nanosphere. Proc. Natl Acad. Sci. USA 107 , 1005 (2010) [3] A.A. Geraci, S. B. Papp, J. Kitching, Short-Range Force Detection Using Optically Cooled Levitated Microspheres. Phys. Rev. Lett. 105, 101101 (2010) [4] M. Arndt and K. Hornberger, Testing the limits of quantummechanical superpositions. Nature Phys. 10, 271(2014) [5] J. Millen, T. Deesuwan, P. F. Barker an J. Anders, Nanoscale temperature measurements using non-equilibrium Brownian dynamics of a levitated nanosphere Nature Nano. 9, 425(2014)