ERC FUNDED PROJECTS

AQSuS aims at experimentally implementing analogue quantum simulation of interacting spin models in two-dimensional geometries. The proposed experimental approach paves the way to investigate a broad range of currently inaccessible quantum phenomena, for which existing analytical and numerical methods reach their limitations. Developing precisely controlled interacting quantum systems in 2D is an important current goal well beyond the field of quantum simulation and has applications in e.g. solid state physics, computing and metrology. To access these models, I propose to develop a novel circuit quantum-electrodynamics (cQED) platform based on the 3D transmon qubit architecture. This platform utilizes the highly engineerable properties and long coherence times of these qubits. A central novel idea behind AQSuS is to exploit the spatial dependence of the naturally occurring dipolar interactions between the qubits to engineer the desired spin-spin interactions. This approach avoids the complicated wiring, typical for other cQED experiments and reduces the complexity of the experimental setup. The scheme is therefore directly scalable to larger systems. The experimental goals are: 1) Demonstrate analogue quantum simulation of an interacting spin system in 1D & 2D. 2) Establish methods to precisely initialize the state of the system, control the interactions and readout single qubit states and multi-qubit correlations. 3) Investigate unobserved quantum phenomena on 2D geometries e.g. kagome and triangular lattices. 4) Study open system dynamics with interacting spin systems. AQSuS builds on my backgrounds in both superconducting qubits and quantum simulation with trapped-ions. With theory collaborators my young research group and I have recently published an article in PRB [9] describing and analysing the proposed platform. The ERC starting grant would allow me to open a big new research direction and capitalize on the foundations established over the last two years.

1 498 515 €

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

This project aims at the development of a novel toolbox of ab-initio methods that approximate the true many-electron wavefunction using systematically improvable perturbation and coupled-cluster theories. The demand and prospects for these methods are excellent given that the highly-accurate coupled-cluster theories can predict atomization- and reaction energies in a wide range of solids and molecules with chemical accuracy (≈43 meV). However, the computational cost involved inhibits their widespread use in the field of materials science so far. A multitude of suggested developments in the present proposal hold the promise to reduce the computational cost beyond what is currently considered possible by the community. These include explicit correlation methods that augment the conventional wavefunction expansion with terms that depend on the electron pair correlation factors. In contrast to the widely-used homogeneous correlation factors, this proposal aims at the investigation of inhomogeneous correlation factors that can also capture van der Waals interactions. Furthermore this proposal seeks to employ a recently developed combination of atom-centered basis functions and plane wave basis sets, maximizing the compactness in the wavefunction expansion. The combination of these ideas bears the potential to reduce the computational cost of coupled-cluster calculations in solids by three orders of magnitude, leading to a breakthrough in the field of highly-accurate ab-initio simulations. As such the study of challenging solid state physics and chemistry problems forms an important part of this proposal. We seek to investigate molecular adsorption and reactions in zeolites and on surfaces, pressure-driven solid-solid phase transitions of two dimensional layered materials and defects in solids. These problems are paradigmatic for van der Waals interactions and strong correlation, and methods that describe their electronic structure accurately are highly sought after.

1 460 826 €

Start date: 2017-07-01, End date: 2022-06-30

The gastrointestinal epithelium is a major physical barrier that protects us from diverse and potentially immunogenic or toxic content. A compromised epithelium results in increased permeability to such content, thus leading to inflammation, immune response, pain, and diseases, such as irritable bowel syndrome and inflammatory bowel disease. A therapeutic strategy that controls inflammation and restores the barrier represents an innovative approach for the prevention and treatment of such diseases. This proposal focuses on how gut peptides regulate epithelial protection and repair, and explores novel therapeutic opportunities by targeting gut receptors that become accessible once the epithelium is compromised. We propose to tackle the overall aim of improving gastrointestinal wound healing via three complementary objectives: (I) to investigate the therapeutic potential of the oxytocin receptor during gastrointestinal inflammation, (II) to elucidate the mechanism of trefoil factor peptide-induced gastrointestinal wound healing, and (III) to discover and characterise novel ligands suitable for epithelial repair. To achieve these objectives, we employ a multidisciplinary approach that includes state-of-the-art peptide synthesis, scaffold grafting, pharmacology, gut stability and wound healing assays, and inflammatory mouse models. We will develop probes to study the mechanisms of action at a molecular level that is not possible with current tools, and explore the biological diversity of venoms for novel therapeutic leads. This project will significantly advance our understanding of epithelial protection/repair and reveal drug targets that treat the source of the problems rather than the symptoms. This project has the potential to change the way we think about treating gut disorders and how to develop peptide therapeutics, and it will pave the way towards the intriguing and longer-term goal of modulating the central nervous system via the gut-brain axis.

1 487 396 €

Start date: 2017-09-01, End date: 2022-08-31

Since more than 50 years, computer vision has been a very active research field but it is still far away from the abilities of the human visual system. This stunning performance of the human visual system can be mainly contributed to a highly efficient three-layer architecture: A low-level layer that sparsifies the visual information by detecting important image features such as image gradients, a mid-level layer that implements disocclusion and boundary completion processes and finally a high-level layer that is concerned with the recognition of objects. Variational methods are certainly one of the most successful methods for low-level vision. However, it is very unlikely that these methods can be further improved without the integration of high-level prior models. Therefore, we propose a unified mathematical framework that allows for a natural integration of high-level priors into low-level variational models. In particular, we propose to represent images in a higher-dimensional space which is inspired by the architecture for the visual cortex. This space performs a decomposition of the image gradients into magnitude and direction and hence performs a lifting of the 2D image to a 3D space. This has several advantages: Firstly, the higher-dimensional embedding allows to implement mid-level tasks such as boundary completion and disocclusion processes in a very natural way. Secondly, the lifted space allows for an explicit access to the orientation and the magnitude of image gradients. In turn, distributions of gradient orientations – known to be highly effective for object detection – can be utilized as high-level priors. This inverts the bottom-up nature of object detectors and hence adds an efficient top-down process to low-level variational models. The developed mathematical approaches will go significantly beyond traditional variational models for computer vision and hence will define a new state-of-the-art in the field.

1 473 525 €

Start date: 2015-06-01, End date: 2020-05-31