Ultracold atoms coupled to micro- and nanomechanical oscillators: towards hybrid quantum systems

Tobias Kampschulte

Montoya Monge, A Cris

Airlia Shaffer, Yogesh Sharad Patil, Hil Fung Harry Cheung +5 more

David Hunger, Stephan Camerer, Theodor W. Hänsch +8 more

This work investigates different coupling mechanisms between ultracold atoms and mechanical oscillators. In a first experiment, atom-surface force is used to couple the vibrations of a mechanical cantilever to the motion of a Bose-Einstein condensate in a magnetic microtrap on a chip. The atoms are trapped at sub-micrometer distance from the cantilever surface. Coupling is used to read out the cantilever vibrations with the atoms. Coupling via surface forces could be employed to couple atoms to molecular-scale oscillators such as carbon nanotubes. In a second experiment, coupling via a 1D optical lattice that is formed by a laser beam retroreflected from the cantilever tip. The optical lattice serves as a transfer rod which couples vibrations of the cantilever to the atoms and vice versa.

Chaitanya S. Joshi

David Hunger, Stephan Camerer, Maria Korppi +3 more

In this article we discuss and compare different ways to engineer an interface between ultracold atoms and micro- and nanomechanical oscillators. We start by analyzing a direct mechanical coupling of a single atom or ion to a mechanical oscillator and show that the very different masses of the two systems place a limit on the achievable coupling constant in this scheme. We then discuss several promising strategies for enhancing the coupling: collective enhancement by using a large number of atoms in an optical lattice in free space, coupling schemes based on high-finesse optical cavities, and coupling to atomic internal states. Throughout the manuscript we discuss both theoretical proposals and first experimental implementations.