Theoretical quantum physics

Welcome to the theoretical quantum physics group
Our research interest is the investigation of ultracold atomic gases and condensed matter system.

Research

The research of the group lies in the area of theoretical quantum physics. Our interest are complex phenomena which emerge by the interplay of many particles. Experimental realizations of such complex quantum systems are for example ultracold atomic gases, hybrid atom-light systems or quantum materials. Our research tries to overcome using numerical and analytical methods the challenges of the theoretical description of such quantum many body systems, of their intriguing quantum phases, and of their collective phenomena.

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© A. Sheikhan

Ultracold quantum gases

In recent years significant advances in the field of ultra cold atoms have facilitated the production of dilute quantum degenerate gases and have culminated in engineering quantum many-body systems with tunable interactions and geometries. The vibrant interplay between cold atomic gases and condensed matter physics has triggered a new wave of research in this field both experimentally and theoretically. Generic condensed matter systems are mimicked with atoms optical lattices, which are lattice potentials created from standing wave laser potentials.

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© arxiv:2208.09346

Solid state physics

Materials have often very complex structures. Electrons are moving on the background formed from the ion core.  The interaction between electrons is of great importance. For example quasi-one dimensional strongly interacting spin structures have been found in different organic compounds and open the way to investigate the strong quantum fluctuations in low dimensions. We investigate the properties of low dimensional materials. One example is the fascinating transition of a Luttinger liquid in weakly coupled spin ladders to a Bose-Einstein condensation.

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© PhysRevResearch.2.043255

Method development

The realization of strongly correlated systems in and out of equilibrium in quantum gases and in nanostructures poses interesting questions which can be tackled theoretically only using state of the art methods. We apply different analytical and numerical methods to get insights into the physics of these systems. One method which has been developed by us is for example the numerical adaptive time-dependent density matrix renormalization group method well suited to investigate the dynamics of low dimensional systems.

Collaborations and funding

Our group takes active part in collaborative research and third party funding. Here we list a selection.

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© TR185

SFB/TR 185 "OSCAR": Open System Control of Atomic and Photonic Matter

The collaborative research center OSCAR will explore the physics of open systems, i.e. the physics resulting from external time-dependent drive and coupling to tailored reservoirs, in a comprehensive way across different experimental platforms.

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© CRC1238

SFB1238: Control and Dynamcis of Quantum Materials

The collaborative research center aims at exploring, understanding, developing, and utilizing quantum materials to gain deliberate control of the physical properties of these materials and to understand their dynamics, explore driven states of matter, and enable new functionalities.

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© erc

Phonton: Phon(t)on-induced phase transitions

We aim to advance the general theoretical understanding of photo-induced phase transitions both in the field of solid state
physics and quantum optics. In particular, we will focus on the design and investigation of photo-induced transitions.

Outreach: Kita project

In order to suppor the scientific curiousity of kids, we have developed different programs in order to perform in Kitas. These programs are tailored to address in all kids (including girls) and let them experience the marvelous world of science.

Contact

Avatar Kollath

Prof. Dr. Corinna Kollath

2.027

Nußallee 12

53115 Bonn

Avatar Vorobjova

Ilona Vorobjova

2.023

Nußallee 12

53115 Bonn

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