Institute of Physics of Materials AS CR, v. v. i. > Groups > Multiscale Modelling and Measurements of Physical Properties

Multiscale Modelling and Measurements of Physical Properties

Headdoc. Ing. Roman Gröger, Ph.D.
E-mail [javascript protected email address]
Phone number+420 532 290 448
Room307



The main purpose of our research activities is to elucidate how functional properties of materials depend on their underlying atomic structure, types of crystal lattice defects and their spatial arrangement, dimensionality of nanostructures and surface properties. We currently focus on heteroepitaxial semiconductor films based on III-nitrides (2D structures, thickness 10-1000 nm), magnetic nanoparticles (Fe3O4, nanocubes 10-50 nm), aggregates of magnetic nanoparticles with low fractal dimensions (D <2) and macroscopic low-temperature behavior of transition metals. This research is carried out using a wide range of theoretical models (DFT, atomic models based on empirical and semi-empirical potentials, Monte Carlo, Landau-Ginzburg, cellular automata, Master equation), which are combined with experimental studies using electron microscopy (TEM, STEM, SEM, EBIC, EBSD), scanning probe microscopy (AFM, MFM, CPEM). We are developing several theoretical models for interpretations of the EBIC current, magnetic diffraction spectra, properties of magnetic nanoparticles and yield criteria for predictions of the onset of plastic deformation in bcc and hcp metals.



Research directions:



  • elucidation of the origin of threading dislocations in III-nitride semiconductor heterostructures

  • formulation of ionic-covalent semi-empirical potentials for studies of extended defects in III-nitrides

  • synthesis, characterization and functionalization of nanoparticles for biology

  • development of equipments for measurements of specific absorption rates of magnetic nanoparticles in alternating magnetic fields

  • characterization of functional properties of materials using TEM (STEM), SEM (EBSD, EBIC), SPM (AFM, MFM, nanoEBIC, CPEM)

  • theoretical models for interpretations of EBIC contrast and of magnetic neutron diffraction spectra

  • experimental and theoretical studies of plastic deformation of bcc metals (V, Nb, Ta, Mo, W) incl. the effects of magnetism (Cr, Fe), and of hcp metals (Mg)

  • elucidation of the mechanisms of plastic deformation in high entropy alloys CoCrFeMnNi and in precipitation-strengthened FeNiCr steels

  • formulation of mesoscopic models of self-organization and pattern formation in correlated microstructural domains


Collaborations



  • University of Cambridge (UK)

  • ON Semiconductor (Czechia, Belgium)

  • CzechNanoLab/CEITEC (Czechia)

  • Istituto Italiano di Tecnologia (Italy)

  • Paul Scherrer Institut (Switzerland)

  • University of Pennsylvania (USA)

  • ICAMS and Ruhr-Universität Bochum (Germany)

  • Materials Growth & Measurement Laboratory (Czechia)


Researchers


NamePhone numbersRoomsE-mail
Mgr. Jan Fikar, Ph.D. +420 532 290 429421 [javascript protected email address]
Mgr. Andrej Ostapovec, Ph.D. +420 532 290 429421 [javascript protected email address]

Phd students


NamePhone numbersRoomsE-mail
Ing. Zuzana Kavčiaková +420 532 290 451308 [javascript protected email address]
Ing. Jakub Pongrácz +420 532 290 451308 [javascript protected email address]
Mgr. Tereza Sojková +420 532 290 451308 [javascript protected email address]
M.Tech. Ritu Verma +420 532 290 461427 [javascript protected email address]
M.Tech. Ankit Yadav +420 532 290 451308 [javascript protected email address]


Project numberNameInvestigator
CZ.01.1.02/0.0/0.0/20_358/0023778 Correlative measurements of the magnetic properties of surfacedoc. Ing. Roman Gröger, Ph.D.
8J19UA037 Non-Schmid behavior of dislocations in magnesium and its alloysMgr. Andrej Ostapovec, Ph.D.
19-23411S Interplay of plasticity and magnetism in alpha-iron and chromiumdoc. Ing. Roman Gröger, Ph.D.
763685 BACK FOR THE FUTURE (CZ)doc. Ing. Roman Gröger, Ph.D.
LQ1601 CEITEC 2020doc. Ing. Luboš Náhlík, Ph.D.
CZ.1.05/1.1.00/02.0068 CEITEC – Central European Institute of Technologydoc. Ing. Luboš Náhlík, Ph.D.
P204/10/0255 Calculation of the Peierls barrier in bcc metals and its dependence on stressdoc. Ing. Roman Gröger, Ph.D.
Marie-Curie International Reintegration Grant (IRG), No. 247705 “MesoPhysDef” Mesoscopic framework for modeling physical processes in multiphase materials with defectsdoc. Ing. Roman Gröger, Ph.D.

ALL PROJECTS

MightyEBIC 2.0 (Ephemeron Labs)

Contact person: doc. Ing. Roman Gröger, Ph.D.
Scan controller and data acquisition interface for making quantitative Electron Beam Induced Current (EBIC) measurements.

SPM LiteScope (NenoVision)

Contact person: doc. Ing. Roman Gröger, Ph.D.
Scanning Probe Microscope (SPM) designed for easy integration into the Scanning Electron Microscopes. The combination of complementary AFM and SEM techniques enables to use the advantages of both commonly used microscopy techniques. LiteScope incorporates a unique imaging technique "Correlative Probe and Electron Microscopy (CPEM)" enabling simultaneous acquisition of AFM and SEM data. LiteScope and the CPEM technology allow sample analysis in a way that was previously difficult or impossible by the two imaging technologies simultaneously.

3D Printer Prusa i3 MKS3+ & MMU2S (Prusa Research)

Contact person: doc. Ing. Roman Gröger, Ph.D.
The Prusa i3 MK3S+ 3D printer is the successor to the successful MK2 model. The main advantages of the MK3S+ include a redesigned extruder, a range of sensors and smart features.


2023

Kloenne Z., Couzinié J., Heczko M., Gröger R., Viswanathan G., Clark W., Fraser H.: On the bcc/B2 interface structure in a refractory high entropy alloy. Scr. Mater. 223 (2023) 115071

Máthis K., Farkas A., Knapek M., Ostapovec A., Farkas G., Németh G., Harcuba P., Drozdenko D.: The influence of gadolinium concentration on the twin propagation rate in magnesium alloys. J. Alloys Comp. 948 (2023) 169635

Holzer J., Husťák M., Hegrová J., Gröger R.: Grain coarsening of columnar iron polycrystals by repetitive cold work and annealing. Metall. Mater. Trans. A 54 (2023) 439-449

Gröger R., Holzer J., Kruml T.: Twinning and antitwinning in body-centered cubic metals. Comp. Mater. Sci. 216 (2023) 111874



2022

Svoboda J., Bořil P., Holzer J., Luptáková N., Jarý M., Mašek B., Dymáček P.: Substantial Improvement of High Temperature Strength of New-Generation Nano-Oxide-Strengthened Alloys by Addition of Metallic Yttrium. Materials 15 (2022) 15020504

Bajtošová L., Křivská ., Králík ., Veselý J., Hanuš J., Harcuba P., Fikar J., Yadav A., Cieslar M.: Deformation mechanisms of Al thin films: In-situ TEM and molecular dynamics study. Scr. Mater. 215 (2022) 114688

Svoboda J., Gamanov Š., Bártková D., Luptáková N., Bořil P., Jarý M., Mašek B., Holzer J., Dymáček P.: The Optimization of Mechanical Alloying Conditions of Powder for the Preparation of a Fe-10Al-4Cr-4Y2O3 ODS Nanocoposite. Materials 15 (2022) 9034

Holzer J., Gamanov Š., Luptáková N., Dlouhý A., Svoboda J.: Coarsening Kinetics of Y2O3 Dispersoid in New Grade of Fe-Al-Cr-Based ODS Alloy. Metals 12 (2022) 12020210

Gamanov Š., Holzer J., Roupcová P., Svoboda J.: High temperature oxidation kinetics of Fe 10Al 4Cr 4Y2O3 ODS alloy at 1200 1400 C. Corros. Sci. 206 (2022) 110498

Gröger R.: Origin of variable propensity for anomalous slip in body-centered cubic metals. Model. Simul. Mater. Sci. Eng. 30 (2022) 085007

Ostapovec A., Verma R., Serra A.: Unravelling the nucleation and growth of {1 1 -2 2} twins. Scr. Mater. 215 (2022) 114730

Vrchovecká K., Weiser A., Přibyl J., Kuta J., Holzer J., Pávková Goldbergová M., Sobola D., Dlouhý A.: A release of Ti-ions from nanostructured titanium oxide surfaces. Surfaces and Interfaces 29 (2022) 101699

Pizúrová N., Buršík J., Sojková T., Roupcová P., Schneeweiss O.: Magnetic properties and morphology of ultra-small iron oxide nanoparticles. J. Phys.: Conf. Series 2315 (2022) 012023

Dymáček P., Kocich R., Kunčická L., Jarý M., Luptáková N., Holzer J., Mašek B., Svoboda J.: Processing of top creep and oxidation resistant Fe-Al based ODS alloys. Procedia Struct. Integr. 42 (2022) 1576-1583

Verma R., Král L., Ostapovec A.: Faceting of {11-26} twin interfaces in rolled pure magnesium. Philos. Mag. 102 (2022) 861-874



2021

Pal-Val P., Vatazhuk O., Ostapovec A., Král L., Pinc J.: Thermoactivated Dislocation Motion in Rolled and Extruded Magnesium: Data of the Low-Temperature Acoustic Experiment . Metals 11 (2021) 1647

Tinoco Navarro H., Holzer J., Pikálek T., Sobota J., Fořt T., Matějka M., Kruml T., Hutař P.: Determination of the yield stress in Al thin film by applying bulge test. Journal of Physics: Conference Series 1777 (2021) 012030

Ostapovec A., K. K., Máthis K., Šiška F.: Interaction of Migrating Twin Boundaries with Obstacles in Magnesium. Metals 11 (2021) 154

Gröger R.: Symmetry-adapted single crystal yield criterion for non-Schmid materials. Int. J. Plast. 146 (2021) 103101

Holzer J., Marshall A., Stejskal P., Stephens C., Vystavěl T.: Large area EBSD mapping using a tilt-free configuration and direct electron detection sensor. Microscopy and Microanalysis 27 (2021) 1832-1835

Marshall A., Holzer J., Stejskal P., Stephens C., Vystavěl T., Whiting M.: The EBSD spatial resolution of a Timepix-based detector in a tilt-free geometry. Ultramicroscopy 226 (2021) 113294

Vacek P., Frentrup M., Lee L., Massabuau F., Kappers M., Wallis D., Gröger R., Oliver R.: Defect structures in (001) zincblende GaN/3C-SiC nucleation layers. J. Appl. Phys. 129 (2021) 155306

Heczko M., Mazánová V., Gröger R., Záležák T., Hooshmand M., George E., Mills M., Dlouhý A.: Elemental segregation to lattice defects in the CrMnFeCoNi high-entropy alloy during high temperature exposures. Acta Mater. 208 (2021) 116719

Bajtošová L., Králík ., Křivská ., Veselý J., Fikar J., Cieslar M.: In-situ TEM deformation of free-standing thin films and molecular dynamics simulations. AIP Conference Proceedings 2411 (2021) 030002

Tinoco Navarro H., Hutař P., Kruml T., Holzer J.: Modeling of elastoplastic behavior of freestanding square thin films under bulge testing. Acta Mech. 232 (2021) 2715-2731

Kvashin N., Ostapovec A., Anento N., Serra A.: On the migration of {332}<110> tilt grain boundary in bcc metals and further nucleation of {112} twin. Comp. Mater. Sci. 196 (2021) 110509

Holzer J., Chlup Z., Kruml T., Gröger R.: Plastic deformation of magnetically isotropic Cr single crystals compressed at 77 K. Int. J. Plast. 138 (2021) 102938

Gröger R., Šremr J., Vydrová J.: Uniqueness and stability of activated dislocation shapes in crystals. Model. Simul. Mater. Sci. Eng. 29 (2021) 025006


all publications