ERC FUNDED PROJECTS

The attoclock is a powerful, new, and unconventional tool to study fundamental attosecond dynamics on an atomic scale. We established its potential by using the first attoclock to measure the tunneling delay time in laser-induced ionization of helium and argon atoms, with surprising results. Building on these first proof-of-principle measurements, I propose to amplify and expand this tool concept to explore the following key questions: How fast can light liberate electrons from a single atom, a single molecule, or a solid-state system? Related are more questions: How fast can an electron tunnel through a potential barrier? How fast is a multi-photon absorption process? How fast is single-photon photoemission? Many of these questions will undoubtedly spark more questions – revealing deeper and more detailed insights on the dynamics of some of the most fundamental and relevant optoelectronic processes. There are still many unknown and unexplored areas here. Theory has failed to offer definitive answers. Simulations based on the exact time-dependent Schrödinger equation have not been possible in most cases. Therefore one uses approximations and simpler models to capture the essential physics. Such semi-classical models potentially will help to understand attosecond energy and charge transport in larger molecular systems. Indeed the attoclock provides a unique tool to explore different semi-classical models. For example, the question of whether electron tunneling through an energetically forbidden region takes a finite time or is instantaneous has been subject to ongoing debate for the last sixty years. The tunnelling process, charge transfer, and energy transport all play key roles in electronics, energy conversion, chemical and biological reactions, and fundamental processes important for improved information, health, and energy technologies. We believe the attoclock can help refine and resolve key models for many of these important underlying attosecond processes.

2 319 796 €

Start date: 2013-03-01, End date: 2018-02-28

My research encompasses the application of novel methods and strategies in the field of low energy particle physics. The goal of the presented program is to lead an independent and highly competitive experiment to search for a CP violating neutron electric dipole moment (nEDM), as well as for new exotic interactions using highly sensitive neutron and proton spin resonance techniques. The measurement of the nEDM is considered to be one of the most important fundamental physics experiments at low energy. It represents a promising route for finding new physics beyond the standard model (SM) and describes an important search for new sources of CP violation in order to understand the observed large baryon asymmetry in our universe. The main project will follow a novel concept based on my original idea, which plans to employ a pulsed neutron beam at high intensity instead of the established use of storable ultracold neutrons. This complementary and potentially ground-breaking method provides the possibility to distinguish between the signal due to a nEDM and previously limiting systematic effects, and should lead to an improved result compared to the present best nEDM beam experiment. The findings of these investigations will be of paramount importance and will form the cornerstone for the success of the full-scale experiment intended for the European Spallation Source. A second scientific question will be addressed by performing spin precession experiments searching for exotic short-range interactions and associated light bosons. This is a vivid field of research motivated by various extensions to the SM. The goal of these measurements, using neutrons and protons, is to search for additional interactions such new bosons mediate between ordinary particles. Both topics describe ambitious and unique efforts. They use related techniques, address important questions in fundamental physics, and have the potential of substantial scientific implications and high-impact results.

1 404 062 €

Start date: 2017-04-01, End date: 2022-03-31

Elementary particle physics is entering a spectacular new era in which experiments at the Large Hadron Collider (LHC) at CERN will soon start probing some of the deepest questions in physics, such as: Why is gravity so weak? Do elementary particles have substructure? What is the origin of mass? Are there new dimensions? Can we produce black holes in the lab? Could there be other universes with different physical laws? While the LHC pushes the energy frontier, the unprecedented precision of Atom Interferometry, has pointed me to a new tool for fundamental physics. These experiments based on the quantum interference of atoms can test General Relativity on the surface of the Earth, detect gravity waves, and test short-distance gravity, charge quantization, and quantum mechanics with unprecedented precision in the next decade. This ERC Advanced grant proposal is aimed at setting up a world-leading European center for development of a deeper theory of fundamental physics. The next 10 years is the optimal time for such studies to benefit from the wealth of new data that will emerge from the LHC, astrophysical observations and atom interferometry. This is a once-in-a-generation opportunity for making ground-breaking progress, and will open up many new research horizons.

2 200 000 €

Start date: 2009-05-01, End date: 2014-04-30

Over the last decade, cold atomic gases have become one of the best controlled quantum system. This novel, synthetic material can be shaped at the microscopic level to mimic a wide range of models, and simulate the universal physics that these models describe. This project pioneers a new approach to quantum simulations, jumping from cold atoms materials into the realm of devices: systems carved out of cold gases, separated by interfaces, connected to each other and allowing for a controlled driving. At the heart of this approach is the study of transport of atoms at the quantum level. Our devices will allow for the measurement of the universal conductance of quantum critical systems or other many-body states. They will feature interfaces and contacts where new types of localized states emerge, such as the one proposed to explain the long-standing question of the “0.7 anomaly” in quantum point contacts. They will also allow for a new type of engineering, where currents of particles, spin or entropy can be controlled and directed in order to perform operations such as cooling. This research will be possible thanks to the development of a new apparatus, capable of detecting in a non-destructive way tiny atomic currents, such as the one driven through single mode quantum conductors. It will combine an optical cavity for high efficiency optical detection, and high optical resolution optics allowing for manipulations and patterning at the scale of the wave function of individual particles.

1 454 258 €

Start date: 2017-02-01, End date: 2022-07-31