Macroscopic quantum states of mechanical oscillators have been proposed
as quantum sensors and for tests of quantum mechanics in unprecedented
regimes [1]. In the field of cavity optomechanics, a mechanical
oscillator — such as a membrane or a levitated nanoparticle — is coupled
to an optical or microwave resonator, and the interaction between light
and motion can be harnessed to reach the quantum regime for the
oscillator’s center-of-mass motion [2]. However, such experiments are
typically limited to the preparation of Gaussian states because they
operate in a regime in which the photon-phonon interaction is linearized.
One route to non-Gaussian states is to introduce a nonlinearity via a
single cold atom or ion [3]. I will present an experimental platform
under development in which we plan to couple both the center-of-mass
motion of a silica nanoparticle and a dipole transition of a single
calcium ion to an optical cavity. As a first step, we have recently
demonstrated techniques for loading and charging nanoparticles in a Paul
trap under ultra-high-vacuum conditions [4] as well as cooling of the
particle’s secular motion via electrical and optical feedback. Looking
forward, I will discuss the role of trapped ions and the advantages of
ion traps for quantum optomechanical experiments.
[1] F. Fröwis, P. Sekatski, W. Dür, N. Gisin, and N. Sangouard, Rev.
Mod. Phys. 90, 025004 (2018)
[2] M. Aspelmeyer, T. J. Kippenberg, and F. Marquardt, Rev. Mod. Phys.
86, 1391 (2014)
[3] A. C. Pflanzer, O. Romero-Isart, and J. I. Cirac, Phys. Rev. A 88,
033804 (2013)
[4] D. S. Bykov, P. Mestres, L. Dania, L. Schmöger, T. E. Northup, Appl.
Phys. Lett. 115, 034101 (2019)