ERC FUNDED PROJECTS

Understanding the physical processes that control the life-cycle of the interstellar medium (ISM) is one of the key themes in the astrophysics of galaxies today. This importance originates from the role of the ISM as the birthplace of new stars, and therefore, as an indivisible component of galaxy evolution. Exactly how the conversion of the ISM to stars takes place is intricately linked to how the internal structure of the cold, molecular clouds in the ISM forms and evolves. Despite this pivotal role, our picture of the molecular cloud structure has a fundamental lacking: it is based largely on observations of low-mass molecular clouds. Yet, it is the massive, giant molecular clouds (GMCs) in which most stars form and which impact the ISM of galaxies most. I present a program that will fill this gap and make profound progress in the field. We have developed a new observational technique that provides an unparalleled view of the structure of young GMCs. I also have developed a powerful tool to study the most important structural characteristics of molecular clouds, e.g., the probability distribution of volume densities, which have not been accessible before. With this program, the full potential of these tools will be put into use. We will produce a unique, high-fidelity column density data set for a statistically interesting volume in the Galaxy, including thousands of molecular clouds. The data set will be unmatched in its quality and extent, providing an unprecedented basis for statistical studies. We will then connect this outstanding observational view with state-of-the-art numerical simulations. This approach allows us to address the key question in the field: Which processes drive the structure formation in massive molecular clouds, and how do they do it? Most crucially, we will create a new, observationally constrained framework for the evolution of the molecular cloud structure over the entire mass range of molecular clouds and star formation in the ISM.

1 266 750 €

Start date: 2016-02-01, End date: 2021-01-31

Micro- and nano-mechanical oscillators with high quality (Q)-factors have gained much interest for their capability to sense very small forces. Recently, this interest has exponentially grown owing to their potential to push the current limits of experimental quantum physics and contribute to our further understanding of quantum effects with large objects. Despite recent advances in the design and fabrication of mechanical resonators, their Q-factor has so far been limited by coupling to the environment through physical contact to a support. This limitation is foreseen to become a bottleneck in the field which might hinder reaching the performances required for some of the envisioned applications. A very attractive alternative to conventional mechanical resonators is based on optically levitated nano-objects in vacuum. In particular, a nanoparticle trapped in the focus of a laser beam in vacuum is mechanically disconnected from its environment and hence does not suffer from clamping losses. First experiments on this configuration have confirmed the unique capability of this approach and demonstrated the largest mechanical Q-factor ever observed at room temperature. The QnanoMECA project aims at capitalizing on the unique capability of optically levitating nanoparticles to advance the field of optomechanics well beyond the current state-of-the-art. The project is first aimed at bringing us closer to ground-state cooling at room temperature. We will also explore new paradigms of optomechanics based on the latest advances of nano-optics. The unique optomechanical properties of the developed systems based on levitated nanoparticles will be used to explore new physical regimes whose experimental observation has been so far hindered by current experimental limitations.

1 987 500 €

Start date: 2015-10-01, End date: 2020-09-30

"This is an interdisciplinary proposal which concerns physics of ultracold atoms and quantum information on one side, and high energy and condensed matter physics on the other. The main objectives are: i) to identify experimentally feasible ultracold atom systems that may serve as quantum simulators of, or exhibit physics relevant for some challenging high energy systems and/or quantum gauge theories; ii) to study these ultracold atom systems, their properties and possibilities of control them for applications in quantum information and quantum metrology that go beyond the high energy physics and quantum simulations; iii) to make very concrete experimental proposals of preparation, manipulation and detection of such systems. In particular, it is planned to investigate: A) ultracold atoms in artificial non-Abelian gauge fields, and non-Abelian integer and fractional Hall effects; B) ultracold atoms with Dirac like dispersion relations (as in relativistic field theories and/or graphene in condensed matter); C) ultracold atoms in polymerized geometries, i.e. in lattices of weakly coupled groups of neighbouring sites (plaquettes); D) ultracold gases in frustrated geometries that can mimic quantum spin liquids, that in turn are often described by Abelian discrete gauge theories; E) ultracold gases with 3- or 4-atom interactions that can serve as simulators of Abelian lattice gauge theories; F) the ultimate, but rather risky and speculative objective would be to find the possibilities of realizing quantum simulators of non-Abelian gauge theories, i.e. to identify the dynamical degrees of freedom of ""gluons"" and to distinguish them from that of matter fields. Expected results are: i) concrete proposals to simulate quantum gauge theories;, ii) better understanding of quantum gauge theories with ultracold atoms, iii) discovery of novel types of quantum gauge field systems; iv) novel systems for robust quantum information processing and metrology."

1 400 000 €

Start date: 2008-11-01, End date: 2013-12-31

This project focuses on the realization and application of trapped Rydberg ions for quantum information processing and quantum simulation. It will bring together two prospective quantum computational systems: trapped ions and Rydberg atoms. Joining them will form a novel quantum system with advantages from both sides. This approach will open a new path of investigation for quantum computing and simulation and will allow investigation of different physical qualities not yet addressed in the existing systems. In particular, it promises to speed up entangling interactions by three orders of magnitude and to extend the interaction distance by at least a factor of two between neighbouring ions. The higher speed of entangling interactions would allow the execution of more complex quantum algorithms before decoherence destroys the stored quantum information. The increased coupling distance would enable the controlled interaction of neighbouring ions which are trapped individually. This would allow setting up a quantum computational system formed by a Coulomb crystal or a two-dimensional array of individually trapped ions. Such qualities make trapped Rydberg ions a powerful alternative approach for scalable quantum information processing. In particular, a string, crystal or two-dimensional array of interacting trapped Rydberg ions can be used for simulations of complex quantum systems intractable by classical computers.

1 499 955 €

Start date: 2012-02-01, End date: 2017-01-31