Katedra fyziky kondenzovaných látek

The main direction of the research performed at our department lies in studies of the structure and electronic properties of materials. Structure and microscopic electronic properties of thin films, magnetic multilayers and intermetallic compounds with f- and d-electrons are investigated by methods using scattering of X-rays, synchrotron radiation and neutron beams. Bulk material properties, especially the magnetic behaviour, transport, thermodynamic and cohesive properties, phase transitions and diffusion processes are investigated over a broad range of temperatures, external pressures and magnetic fields. Modern materials like nanocrystalline powders, two-dimensional surface structures, liquid crystals and carbon composites are studied in co-operation with other laboratories. Theoretical studies of quantum coherence in semiconductor alloys excited by femtosecond pulses, mesoscopic theory of wear and physics of granular systems complete our fields of interest, together with computing materials science focused on the electron structure of intermetallic compounds, modern oxides and borocarbides of rare-earth and transition metals.

The Department is a part of Faculty of Mathematics and Physics of Charles University, and it is itself divided into three sections: the X-ray Group, Group of Magnetic Studies, and Group of Theoretical Physics.

X-ray Group

The main direction of the research performed at our department lies in studies of the structure and electronic properties of materials. Structure and microscopic electronic properties of thin films, magnetic multilayers and intermetallic compounds with f- and d-electrons are investigated by methods using scattering of X-rays, synchrotron radiation and neutron beams. Bulk material properties, especially the magnetic behaviour, transport, thermodynamic and cohesive properties, phase transitions and diffusion processes are investigated over a broad range of temperatures, external pressures and magnetic fields. Modern materials like nanocrystalline powders, two-dimensional surface structures, liquid crystals and carbon composites are studied in co-operation with other laboratories. Theoretical studies of quantum coherence in semiconductor alloys excited by femtosecond pulses, mesoscopic theory of wear and physics of granular systems complete our fields of interest, together with computing materials science focused on the electron structure of intermetallic compounds, modern oxides and borocarbides of rare-earth and transition metals. 

Group of Magnetic Studies

The Department of Magnetic Properties has been dealing with the lanthanide and actinide (uranium) magnetism since 1970's. Their specific magnetic properties, on which the permanent magnet and information storage industry is based, have been more and more studied in the context of other electronic structure properties (transport, thermodynamic).

Major achievements include elucidation of trends of the U-magnetism in complex intermetallic compounds in 1980's or the discovery and contribution to explanation of the Giant Magnetoresistance phenomenon in some ternary systems in 1990's.
At present, a large scale of various experimental techniques is available at the Department of Magnetic Properties, allowing to investigate magnetic, transport, and thermodynamic phenomena in a wide temperature range down to the millikelvin range, and up to high magnetic fields (14 T). Own research is based on a technology basis, which allows metal purification, single crystal growth, or a hydride synthesis under a high hydrogen pressure. Experimental techniques are accompanied by state-of-the art methods for electronic structure calculations, which include fully relativistic approximations, spin and orbital polarization, which facilitate deeper understanding of observed phenomena, and to some extent even prediction of material-specific properties.
The experimental techniques unvailable in Prague are aceessible through international consortia and collaborations (ESRF Grenoble, ILL Grenoble, NHMFL Tallahassee/Los Alamos). Materials containing transuranium elements Np, Pu, Am are investigated at the Joint Research Centre, Institute for Transuranium Elements in Karlsruhe.
The extended reasearch capabilities have recently more focused on the so-called functional materials and phenomena, as e.g.. the Giant Magnetocaloric Effect, observed for some magnetic materials, which started to be used in cryogenic applications and generally in ecological cooling technologies.
 

Group of Theoretical Physics

The activity of the group is focused on the field of quantum theory of condensed matter. Electron states in crystalline and disordered systems and magnetic properties of solids are studied; special effort is devoted to the electronic structure and electronic processes at surfaces and in magnetic multilayers. These studies are based on ab initio methods implemented in own and overtaken software packages. The method of non-equilibrium Green’s functions is developed in the field of quantum transport with applications to strongly non-equilibrium phenomena due to ultrashort laser pulses and other non-linear processes. Dynamical processes of macroscopic physics have been studied as well, especially dry friction and sound propagation in granular materials. The group has long-term collaborations with institutes of Academy of Sciences in Prague and Brno as well as with research institutes abroad, e.g., with the Center for Computational Materials Science in Vienna.