Collective quantum effects with levitated particles

Research homepage of Uroš Delić

I am an experimental physicist and a Senior Scientist in Prof. Markus Aspelmeyer's group at the University of Vienna. 

My research focuses on quantum control and collective effects in ensembles of trapped solid-state objects.

My research is supported by the Austrian Science Fund (FWF), Austrian Academy of Sciences (ÖAW), John Templeton Foundation, and the Aspelmeyer group.

© Luiza Puiu

25 October 2024

Our study on the linear ultrastrong optomechanical coupling of an optically trapped nanoparticle to an optical cavity is now published in Phys. Rev. Research! In this work, we measure coupling rates of up to 55% of the bare mechanical frequency. Our system exploits the coherent coupling scheme by the transverse drive through the particle, which yields a genuinely linear interaction Hamiltonian. In such a system, as one of the eigenmodes experiences an inverted harmonic potential, the system can reach instability if the coupling rate exceeds 50% of the mechanical frequency. This effect could create squeezed states (see this work for more details).

25 July 2024

Our work on non-Hermitian dynamics of nonreciprocally and nonlinearly coupled optically levitated nanoparticles has just been published in Nature Physics. In this work, we observe PT symmetry breaking by reconstructing the eigenmodes with non-degenerate damping rates. For a larger coupling rate, the system exhibits a collective transition into a mechanical lasing state, where both particles become nonlinear oscillators. Larger arrays of particles will allow us to study nonreciprocal phase transitions or explore novel sensing strategies. Read more about it in our press release or the Nature News & Views article written by Jayadev Vijayan.

© Luiza Puiu

20 June 2024

I received one of the prestigious START Awards from the Austrian Science Fund (FWF), supporting my research with 1.2 million Euros over the next 5 years. This will allow us to build experiments that explore nonreciprocal interactions between optically levitated nanoparticles in the quantum regime. Our research will be hosted by the Institute of Quantum Optics and Quantum Information (IQOQI) Innsbruck of the Austrian Academy of Sciences (ÖAW). Read more about the research questions that we will explore here.

01 February 2023

I have been awarded the ESQ Discovery Grant from the Austrian Academy of Sciences to explore Ultrastrong Cavity Optomechanics with an optically levitated nanoparticle.

22 December 2022

Our work on "Dry launching of silica nanoparticles in vacuum" has been published in AIP Advances! In this work, we show that we can shake off glass nanoparticles as small as 43 nm in radius (we didn't have smaller particles available!) from PTFE microscope slides. Read more.

26 August 2022

Our paper on "Tunable light-induced dipole-dipole interactions between optically levitated nanoparticles" has just been published in Science! Click here to read our press release. I also highly recommend reading the Science Perspective by Julen Simon Pedernales  and the Nature news feature written by Davide Castelvecchi.

08 July 2022

Congratulations to Livia Egyed MSc. for successfully defending her Master thesis "Light-induced dipole-dipole interactions between optically levitated nanoparticles"! Livia will continue working on the topic in the course of her PhD from October.

Contact:

E-mail: uros.delic@univie.ac.at

Faculty of Physics, University of Vienna

Boltzmanngasse 5, 1090 Vienna, Austria

Thanks to: