Nanoparticles levitated in an ion trap: steps toward quantum control

Speaker: Tracy Northup, University of Innsbruck.

Coupling a spin qubit to a mechanical system provides a route to prepare the mechanical system's motion in nonclassical states, such as a Fock state or an entangled state. Such quantum states have already been realized with superconducting qubits coupled to clamped mechanical oscillators. We are interested in achieving an analogous coupling between a spin and a levitated oscillator — namely, a silica nanoparticle in a linear Paul trap — in order to take advantage of a levitated system's extreme isolation from its environment. In this case, we envision an atomic ion as the spin qubit.

I will present recent steps in this direction, including the demonstration of a quality factor above 10^{10}, obtained by confining a nanoparticle under ultra-high vacuum in the absence of light-induced decoherence  [1]. Furthermore, we have trapped a calcium ion and a nanoparticle together in a linear Paul trap, implementing a dual-frequency trapping scheme to address the extreme disparity in charge-to-mass ratio [2]. We will consider future prospects for controlled interactions between ions and nanoparticles in this trap.

References
[1] L. Dania, D. S. Bykov, F. Goschin, M. Teller, A. Kassid, T. E. Northup, Phys. Rev. Lett., in press (2024)
[2] D. S. Bykov, L. Dania, F. Goschin, T. E. Northup, arXiv:2403.02034 (2024)