High-Energy Physics
Quark Ggluon Plasma (QGP) is created in Heavy Ion Collisions at the Relativistic Heavy Ion Collider (RHIC) and LHC. A striking discovery of RHIC is that QGP produced there is strongly coupled and behaves like a nearly perfect fluid with relativistic hydrodynamics being an appropriate description of the observed phenomena. Remarkably, hydrodynamical properties of QGP could be studied using gravitational theory of Black Holes in curved five-dimensional spaces. The fluid/gravity correspondence relates graviton`s absorption by a Black Hole to dissipation taking place in the QGP.
Condensed Matter Theory
As electrons are confined to smaller and smaller spaces, quantum effects and strong correlations among the electrons start to dominate the underlying physics. In this area of research we investigate how such effects influence the electronic properties of miniaturized devices, such as quantum dots (QDs) and quantum point contacts (QPCs), and how such devices can be used to enhance our understanding of quantum mechanics and many-body physics.
Astrophysics and Cosmology
Massive galaxy clusters bend light rays from background sources to form magnified, distorted, and multiple arcs. Using this Gravitational Lensing phenomenon, we can map the Dark Matter distribution of the lens, invisible otherwise. Thanks to the magnification power from lensing we can also access increasingly fainter and high-redshift (earlier) galaxies, and study the evolution of the first generation galaxies and the Reionization of the Universe.
Atomic, Molecular and Optical Physics
Quantum-interference-related phenomena have many implications in physics. Quantum interference between two independent quantum channels in three-level systems gives rise to various coherent phenomena, such as electromagnetically induced transparency (EIT), coherent population trapping (CPT), lasing/gain without inversion (LWI/GWI), enhancement of refraction index, sub- and super-luminal light propagation etc. These phenomena open a wide-range perspective for new type of phase-sensitive spectroscopy. An example is the possibility to get sub-natural line widths (see movie).
Condensed Matter Experimental
In the STM image shown, observed in our lab, we see some disordered white spots. The STM does not have chemical identification capability. Such chemical identification is observed macroscopically using macroscopic magnetic resonance – both of electrons and nuclei. We develop a magnetic resonance technique on the single atom level, observed via a Larmor frequency component in the tunneling current. We identify the type of atoms under the tip using their spectrum – for example the SiC hyperfine spectrum. Preliminary results showed the observation of the nuclear transitions (NMR) with the STM.
Biological and Soft Matter Physics
The impacts of environmental changes on species diversity, and thus on ecosystem function and stability, is a central topic of current ecological research. At the landscape scale, where symmetry breaking vegetation patterns appear, a transition from one pattern state to another may take place (Animation). Using a mathematical modeling approach, we developed a theory of plant communities in water limited system, and are currently using it to highlight mechanisms of species diversity change in response to climate changes and disturbances.