Groß Group

 

We experimentally study synthetic quantum many-body systems formed out of ultracold atoms in optical lattices. This platform provides a very well isolated and fully controlled quantum system, of which the microscopic properties can be tailored in a wide parameter range. We aim at perfecting the control over this system to explore the intriguing dynamics and correlations in quantum many-body systems at the level of single atoms.


Realizing the Hubbard model

The Hubbard model is the most prominent electronic toy model for the electronic degrees of freedom in high temperature superconductors. We aim to study this model in a clean system, thereby performing a quantum simulation of this in certain regimes computationally intractable problem. To this end, we developed a so called quantum gas microscope for fermionic lithium atoms in an optical lattice. The defining property of a quantum gas microscope is the ability to measure single atoms, in our realization even the spin state of single atoms, in the strongly correlated many-body system. This gives access to novel potentially non-local observable, such as string correlators, and we use them to shed new light onto these systems. We aim to explore the equilibrium correlations between spins and holes at the lowest reachable temperatures, as well as their dynamics in controlled out-of equilibrium situations.


Laser controlled long-range interactions

Quantum magnets are not only often used toy models for the many-body physics in real materials, perfect control over them also enables new technologies in the fields of quantum metrology, simulation and information. In magnets, the only degree of freedom is the local spin and non-trivial systems require interaction between spins at a finite distance. A very promising and flexible way to realize such a setting with ultracold atoms in optical lattices is to use state selective laser coupling to Rydberg states. The Rydberg states feature large electron orbits and hence a large polarizability, with results in very strong interactions extending of the distance of several micrometer. This includes several  sites of the optical lattice. Even more, the interaction between the atoms can be tailored by the choice of the Rydberg states and switched almost at will by controlling the laser intensity. We aim to explore the quantum dynamics in such fully controlled quantum magnets and by pushing the limits of control and coherence we aim to realize an artificial quantum system, which can serve as a platform for quantum many-body physics and quantum technologies.

Dr. Christian Groß

Address:

Max Planck Institute of Quantum Optics
Hans-Kopfermann-Str. 1
D-85748 Garching
Germany

Phone: +49 (0)89 / 32905-713
Fax: +49 (0)89 /
32905- 313
Email: christian.gross@mpq.mpg.de

Group webpage