Levitation of solid-state objects is a unique approach to realise (nano- or micro-)mechanical devices with minimal mechanical losses. Besides improved sensing capabilities such systems have the potential for significantly increased coherence time when operated in the quantum regime. Our group combines levitation techniques for optical and magnetic trapping with quantum control via optical or microwave radiation fields. Recently, we have demonstrated optical trapping and cooling of a dielectric sub-micron particle in the standing wave field of a high-finesse Fabry-Perot cavity. In addition, we have been extending our efforts to magnetic and superconducting levitation. We are also combining optical levitation with photonic structures. We have recently demonstrated optical trapping, transport and feedback of dielectric nano-spheres inside hollow-core photonic-crystal fibres. This turns out to be an interesting platform to study non-linear flow-dynamics in micro-channels.         

Publications (selected):

Optical trapping and control of nanoparticles inside evacuated hollow core photonic crystal fibers
D. Grass, J. Fesel, S. G. Hofer, N. Kiesel, M. Aspelmeyer
Appl. Phys. Lett. 108, 221103 (2016)

Cavity cooling of an optically levitated submicron particle
N. Kiesel, F. Blaser, U. Delic, D. Grass, R. Kaltenbaek, M. Aspelmeyer
PNAS USA, vol. 110, no. 35, 14180–14185 (2013)

Large Quantum Superpositions and Interference of Massive Nanometer-Sized Objects
O. Romero-Isart, A. C. Pflanzer, F. Blaser, R. Kaltenbaek, N. Kiesel, M. Aspelmeyer, and J. I. Cirac
Phys. Rev. Lett. 107, 20405 (2011).

Background:

Quantum Magnetomechanics with Levitating Superconducting Microspheres
O. Romero-Isart, L. Clemente, C. Navau, A. Sanchez, J. Cirac
Phys. Rev. Lett. 109, 147205 (2012)

Cavity opto-mechanics using an optically levitated nanosphere
D. E. Chang, C. A. Regal, S. B. Papp, D. J. Wilson, J. Ye, O. Painter, H. J. Kimble, and P. Zoller
Proc. Natl. Acad. Sci. U. S. A. 107, 1005–10 (2010)

Towards Quantum Superposition of Living Organisms
O. Romero-Isart, M. L. Juan, R. Quidant, J. I. Cirac
Quantum V, 1–8 (2010)

Optical trapping and manipulation of neutral particles using lasers
A. Ashkin
World Scientific (2006)

A Superconducting Gravimeter
W. A. Prothero, J. M. Goodkind
Rev. Sci. Instrum. 39, 1257 (1968)