Quantum control of mechanical motion

Preparing massive systems in genuine quantum states is a powerful way to probe the limits of quantum mechanics and to explore questions at the interface of quantum physics, gravity, and the classical world. A central platform for this pursuit is optomechanics, where mechanical motion is controlled and measured through its interaction with light. To realize the most exciting applications of optomechanics — ranging from tests of fundamental physics to novel sensing technologies — mechanical systems must be carefully isolated from their environment, while maintaining well-controlled interactions with light and other systems used to control or probe them, e.g. spins.

Our group develops theoretical models of nanomechanical systems coupled to the electromagnetic field, with a special focus on levitated optomechanics. In these systems, mechanical oscillators are suspended in vacuum, i.e. without any clamping, offering unprecedented levels of control and isolation. We study the mechanisms of motional decoherence in such setups, develop models to create and optimize the interaction of the mechanical motion to additional degrees of freedom such as spins, and propose routes to preparing nonclassical motional states. This research draws on a broad range of theoretical tools, including quantum mechanics, open quantum systems, electrodynamics, and quantum optics. It also relies on close contact with experimental colleagues.

Latest publications in Levitodynamics / Optomechanics

High-purity quantum optomechanics at room temperature
Lorenzo Dania, Oscar Schmitt Kremer, Johannes Piotrowski, Davide Candoli, Oriol Romero-Isart, Carlos Gonzalez-Ballestero, Lukas Novotny, Martin Frimmer
Nature Physics 21, 1603 (2025)

Motional entanglement of remote optically levitated nanoparticles
Nicola Carlon Zambon, Massimiliano Rossi, Martin Frimmer, Lukas Novotny, Carlos Gonzalez-Ballestero, Oriol Romero-Isart, Andrei Militaru
Phys. Rev. A 111, 013521 (2025)

Numerical Simulation of Large-Scale Nonlinear Open Quantum Mechanics
M. Roda-Llordes, D. Candoli, P. T. Grochowski, A. Riera-Campeny, T. Agrenius, J. J. García-Ripoll, C. Gonzalez-Ballestero, O. Romero-Isart
Phys. Rev. Research 6, 013262 (2024)

Cavity-mediated long-range interactions in levitated optomechanics
J. Vijayan, J. Piotrowski, C. Gonzalez-Ballestero, K. Weber, O. Romero-Isart, L. Novotny
Nature Physics (2024)

Quantum electrodynamics with a nonmoving dielectric sphere: quantizing Lorenz-Mie scattering
P. Maurer, C. Gonzalez-Ballestero, O. Romero-Isart
J. Opt. Soc. Am. B 40, 3137 (2023)

More in our publication list