Projects

GA 15-01602S

Nanostructures for optics and photonics will be deposited in crystals and amorphous materials using ion implantation, which offers a many possibilities of the functional devices preparation. We will focus on a more detailed study of single crystal materials and glasses implanted by metal and light ions. The combination of appropriate substrate and implanted ion enables us to prepare materials with the desired properties (optical, electrical). Our intention is to define relation between the nano-particles morphology and the optical properties (band gap, photoluminescence), structural changes and dopant positioning in the host matrix. Energetic ions modifying solid materials will be used for the fundamental study of stopping powers of ions in solid compounds and simultaneously will be provided validation of semi-empirical models used in simulation. The simulations and knowledge of empirical stopping powers are irreplaceable in nanostructure synthesis using ion implantation. Measurement of ion stopping in compounds will be realized using transmission and backscattering ion beam methods.

GA104/09/1269

Silicate glass is one of the most important and widely spread technical materials. It is frequently used in the applications where it is exposed to the particle radiations of different energies. Therefore, it is very important to study the changes in glass caused by the radiation both from technical applications point of view (changes in glass properties) as well as from point of view of glass science (changes in glass structure).The project will perform a systematic investigation of changes in glass structure and properties caused by electrons irradiation in different energy ranges from about 3 keV up to MeV's and by proton irradiation (MeV). The compositional changes and inhomogeneities on the micron scale will be characterized by EPMA. Evolution of structural changes will be studied by XPS, NMR, and Raman spectroscopy. Surface topographies will be characterized by AFM and SEM. Moreover, the molecular dynamics simulations will be used as a theoretical tool for the interpretation of the experimental findings. Chemical durability of glass irradiated with electrons/protons will be established and nanoindentation methods will be used for the characterization of mechanical properties. Expected results may enhance the applicability of glass and improve its limiting properties.

GAP108/11/0958

Complex investigations of point defects in ZnO are proposed in the present project. Positron annihilation spectroscopy (PAS) including also variable energy PAS using slow positron beam will be used as a principal technique for defect studies. State-of-art ab-initio theoretical calculations will be employed for interpretation of PAS data. Defects in ZnO single crystals will be compared with those in epitaxial and nanocrystalline ZnO thin films. Defects studies will be combined with electrical (temperature-dependent Hall effect, deep level transient spectroscopy) and optical (photoluminescence, optical transmission) measurements in order to find a link between predominant defect configurations and specific electrical and optical properties of ZnO samples. Moreover, in the present project we intend to investigate interaction of hydrogen and nitrogen with point defects in ZnO and influence hydrogen and nitrogen on electrical and optical properties. A new UHV chamber for on-line sputtering of ZnO films will be constructed and connected to slow positron beam. This novel setup enables to perform variable energy PAS investigations of thin ZnO films in-situ during film deposition. It gives us an exclusive possibility to investigate formation of defects and incorporation of impurities into ZnO lattice during film growth.

LC06041

Preparation and characterization of prospective materials and structures by energetic radiation, upgrading of experimental base of partners, interconnection of universities and academic institutes in research and student education. Basic research topics will be: Modification of polymers by ion beams, plasma and chemical dotation; Electric properties of semiconductors modified by ion beams; Radiation degradation of selected materials; Development and usage of new types of detectors of ionizing radiation; Latent ion tracks in polymers and their usage in construction of sensors; Nano- and micro-structures based on polymers and carbon allotropes and their usage in bio-medicine; Diffusion processes on metal-dielectric boundaries and selforganization in metal-carbon allotropes systems; New materials for opto-electronics based on LiNbO3, LiTaO3, GaN, SiC and polymers; Modification of metal films and nanoparticles by carboran derivatives and controlled chemical reactions on surfaces.

SPIRIT U1327500299137

The materials doped by erbium ions are currently used for optical signal amplification or generation. Important factors influencing the luminescence properties of a lasing ion is the surounding crystal field. In this project we would like to use the ion-implantation technique followed by subsequent annealing as a useful way to influence the crystal field of implanted ion in LiNbO3, ZnO and special glasses. This project continue in previous projects SPIRIT No. 117 (2011) and RITA No. 025646 (2007-2009).

GA 19-02482S

 GA 18-03346S

Grant No. GA 18-03346S

Provider: GAČR - Grantová agentura České republiky (GACR - Czech Science Foundation) 2019-2021

Proposer: prof. RNDr. Anna Macková Ph.D., ÚJF AV ČR, v. v. i. (NPI of the CAS)

Co-proposer: doc. Ing. Pavla Nekvindová, Ph.D., VŠCHT Praha (UCT Prague)

Title: Optical active centers and microstructuring in ZnO and cubic ZrO₂

The project is dealing with the intentional synthetization of optical active centers using energetic ion beams in ZnO and ZrO₂. Nowadays ZnO is highly attractive material prospective in the form of thin layers or nanowires for nanosized optical devices with functionalized semiconductor surfaces as a recently established breakthrough concept. Both materials are highly resistant to radiation exposure. The ion beam induced defects, color centers, created defect stability and dynamics is mandatory to be studied for the proposed applications as inert matrix for actinide transmutation or optical applications. Both materials will be intentionally modified by ion beam irradiation in the broad spectrum of masses and energies which will be accompanied by detailed structural, optical studies, simulation of ion and matrix ballistic processes induced by ion beams and DFT simulations. The high attention will be paid to the influence of various crystallographic orientations behaviour under ion beam irradiation and its different physical feedback under the ion beam is expected.