Quantum many-body physics with ultracold atoms and molecules: exact dynamics and machine learning 

Dawid Lekowska, Anna Maria (Date of defense: 2022-09-20)

(English) Quantum many-body physics poses a substantial computational challenge resulting from the exponential growth of the wave function complexity and many non-trivial correlations encoded in it. ...

Quantum simulations with ultracold atoms: beyond standard optical lattices 

Hauke, Philipp Hans-Jürgen (Date of defense: 2013-04-05)

Many outstanding problems in quantum physics, such as high-Tc superconductivity or quark confinement, are still - after decades of research - awaiting commonly accepted explanations. One reason is that ...

Quantum Brownian motion revisited : extensions and applications 

Lampo, Aniello (Date of defense: 2018-10-02)

Quantum Brownian motion represents a paradigmatic model of open quantum system, namely a system which cannot be treated as an isolated one, because of the unavoidable interaction with the surrounding ...

Complex systems for quantum technologies 

Braungardt, Sibylle (Date of defense: 2011-07-12)

Exact diagonalization studies of quantum simulators 

Raventós Ribera, David (Date of defense: 2019-04-15)

Understand and tame complex quantum mechanical systems to build quantum technologies is one of the most important scientific endeavour nowadays. In this effort, Atomic, molecular and Optical systems ...

Experimental evidence for the quantum condensation of ultracold dipolar excitons 

Alloing, Mathieu (Date of defense: 2014-05-28)

In this thesis, we report experimental evidence of a "gray" condensate of excitons, as predicted theoretically by M. Combescot et al. Most importantly, the condensate is characterized by the macroscopic ...

Strong-field processes in atoms and polyatomic molecules 

Suárez Rojas, Noslen (Date of defense: 2018-01-23)

In this thesis, we develop a general theory to describe the dynamics of electrons that are ionized when an atom or molecule is exposed to a strong low frequency laser field. Our approach extends and ...

Investigating quantum many-body systems with tensor networks, machine learning and quantum computers 

Kottmann, Korbinian Gebhard (Date of defense: 2022-10-14)

(English) We perform quantum simulation on classical and quantum computers and set up a machine learning framework in which we can map out phase diagrams of known and unknown quantum many-body systems ...

Dynamics of quantum mixtures 

Guenther, Nils Eric (Date of defense: 2021-09-08)

At sufficiently low temperatures, fluids of bosonic particles may undergo a phase transition, below which a Bose-Einstein condensate (BEC) forms. The BEC is one of the most fundamental concepts in ...

Anomalous diffusion : from life to machines 

Muñoz Gil, Gorka (Date of defense: 2020-11-09)

Diffusion refers to numerous phenomena, by which particles and bodies of all kinds move throughout any kind of material, has emerged as one of the most prominent subjects in the study of complex systems. ...