CORDIS - Forschungsergebnisse der EU

Collective effects and optomechanics in ultra-cold matter

Periodic Reporting for period 2 - ColOpt (Collective effects and optomechanics in ultra-cold matter)

Berichtszeitraum: 2019-01-01 bis 2021-06-30

The network “Collective effects and optomechanics in ultra-cold matter” (ColOpt) trained early stage researchers (ESRs) in fundamental science and applications in the areas of cold atom and quantum physics, optical technologies and complexity science. It consists of nine academic nodes and three companies from six European countries, supported by two partners in Brazil and the USA, and ten further non-academic and academic partners in Europe.

Collective, nonlinear dynamics and spontaneous self-organization are abundant in nature, sciences and technology. Building on this interdisciplinary relevance, a particular novelty of ColOpt is the integration of classical and quantum self-organisation. The research program focused on collective interactions of light with laser-cooled cold and quantum-degenerate matter. We explored innovative control of matter through opto-mechanical effects, identified novel quantum phases, investigated light transport in strongly scattering and disordered systems, advanced the associated trapping, laser and optical technologies, thereby enhancing the knowledge in non-equilibrium quantum dynamics and of long-range coupled systems and establishing new concepts in quantum information and simulation.

The work was organised in four scientific work packages with the objectives:
1. To demonstrate novel self-organised spatial states of cold classical and quantum degenerate matter.
2. To implement novel trapping geometries and complex light fields for quantum information.
3. To advance collective scattering and coupled dipole dynamics in dense atomic samples.
4. To advance the supporting laser technology.

The relevance of this work for society emerges from four main strands and motivations:
1. To achieve a deeper understanding of non-equilibrium quantum systems is a major quest from a fundamental point of view, as this underpins our understanding of how quantum systems interface with each other and the classical world.
2. To build new Quantum Technologies on non-trivial quantum aspects is expected to provide a revolution in applications such as secure communication, computation, material science and sensing, often referred to as “second quantum revolution”.
3. To understand complex systems with nonlinear interactions, memory and feedback in physics and to foster the ability to transfer this knowledge to more complex systems in biology, ecology, economy.
4. To provide skilful and responsible researchers, who are able to drive technological innovation, have an understanding of potential impacts and can participate as informed citizens in societal discussions.

The network concluded with the successful training of a cohort of 15 highly skilled innovative and outward-looking researchers able to develop and advance successfully their career in a wide range of industrial, government and academic institutions in the international setting of the European Research Area. The researchers drove scientific and technological progress published in high-reputation journals, engaged in dissemination to the scientific community and to the general public and experienced first steps on the road to leadership and independent scientific endeavour.
The research training rested on network training and the individual research projects as the main pillars. We delivered six network training events mainly for scientific training, progress reports and scientific interaction. Two three-day long residential courses served for transferable skills training and cohort building. The latter was also enhanced by secondments of ESRs within the network constituting an integral and well received part of the research training and research experience. Two further ColOpt-organized events with external participation were a winter school on “Collective effects, structured light and quantum matter” and a workshop on “Collective Effects and Non‐Equilibrium Quantum Dynamics”, both well attended and well received by the community. We further engaged strongly in the promotion of leadership, networking and experiences of young scientists by including a Young Scientist Day in the winter school and supporting and participating in the Young Atomic Opticians Conference in Glasgow June 2018. A ColOpt-wide outreach event to the general public took place at the Glasgow Science Centre in September 2018. ESRs engaged in many further schools, conferences, student societies and outreach events.

All ambitious research projects made good progress. Highlights of results are described in the next section. The scientific output of ColOpt has been disseminated in high-profile journals and conferences. 56 papers are published in journals and conference proceedings, 42% of them are collaborative. Most of the researchers registered on postgraduate research degrees either defended their thesis or are close to it. Three moved already to further industrial employment, two for postdoctoral positions.
ColOpt partners advanced the fundamentals and applications of mesoscopic cold atom physics, out-of-equilibrium quantum physics and quantum technologies and the understanding of complex quantum systems considerably. We highlight the following results:
1. Researchers from the CNRS investigated spatio-temporal instabilities on large, dense clouds of atoms. The work has relevance to achieve large, high density atomic clouds for scattering experiments and quantum technologies but could serve also as laboratory test bed for large scale radiation induced structures in astrophysical context.
2. Researchers from the University of Strathclyde demonstrated that extended and localized optomechanical structures can rotate, if the pump beam is not a simple, uniform plane wave but contains orbital angular momentum. This has relevance for transport properties in self-organised phases and for control of trapping atoms and potentially other nanoparticles.
3. Researchers from the University of Milano studied the vibrational modes of a two atom “molecule”, in which the atoms are bound to each other by light forces. They demonstrate that long-term stability is only possible with an extra cooling mechanism. This has relevance for self-assembled structures enabled by optical binding.
4. Researchers from Toptica and MSquared Lasers advanced automatization and miniaturization of laser systems. This is expected to make quantum sensors more robust, compact and less expensive to enable a broader uptake of quantum technologies.

The cohort of 15 highly-skilled researchers trained will be able to excel in and to drive innovation in a wide range of areas underpinned by STEM skills. In particular, ColOpt researchers are in an excellent position to drive the emerging quantum technologies and the so-called second quantum revolution, an innovation field identified to be crucial for the European economy and research base. The fact that three of twelve beneficiaries of ColOpt are companies provides an important and powerful message on the relevance of inter-sectoral training and interaction and the commitment of industry to contribute to skill development to ESRs.

Awareness of the need and benefits of connecting to different communities and in particular to the general public was an important aim and activity of ColOpt. These experiences equip the ESR well not only being a technically skilled and successful researcher but having social competences and the ability and will to present and defend scientific views in public.
Spatio-temporal dynamics of a large cloud of atoms driven by radiation pressure (project 1.2, CNRS)
Colopt logo
Colopt_ESRs at Outreach Event
Numerical simulation of a spontaneous structure in a cavity (project 2.2, USTRAT)