Welcome to the web home for the Department of Magnetism. The Department of Magnetism is one of ten basic science departments in the Institute of Experimental Physics Slovak Academy of Science. The basic research in our department is devoted to preparation magnetic nanoparticles, magnetic fluids and complex system containing magnetic nanoparticles and study their basic magnetic, structural and dielectric properties with the possibility their technical and biomedicine application.
- MAGNETIC FLUIDS BASED ON TRANSFORMER OILS
(M. Timko, M. Rajňak, P. Kopčanský, Z. Mitróová, K. Paulovičová, T. Tobiáš)
The current progress in high voltage engineering has elevated high demands on the reliability and effectiveness of cooling and insulating media. The aim of our research is to develop alternative types of the media by doping transformer oils with magnetic nanoparticles. By means of a broad range of experimental study we want to contribute to the understanding of the specific mechanism of the thermal transport and enhanced electrical breakdown in the modified transformer oils.
- NANOPARTICLES FOR BIOAPPLICATIONS
(M. Koneracká, V. Závišová, P. Kopčanský, M. Kubovčíková, I. Antal)
Recently magnetic particles have attracted great research interests due to their potential applications in biomedicine and biotechnology. In our research we deal with not only synthesis of magnetic nanoparticles but also fully characterization of basic physical properties (magnetic properties, morphology and size distribution) of magnetic nanoparticles. Our aim is also functionalization of spherical shaped of magnetic nanoparticles by biocompatible materials with the aim to use the nanoparticles in magnetic drug delivery. Furthermore, we are able to immobilize of specific antibody to functionalised magnetic nanoparticles that are able to detect cancer cells.
- LIQUID CRYSTALS AND FERRONEMATICS
(P. Kopčanský, N. Tomašovičová, M. Timko, V. Gdovinová, J. Majorošová)
Currently, one of the hot topics of the worldwide research is to design nanomaterials that are capable to assemble into functional superstructures in multiple direction. Liquid crystals themselves are prominent example of materials in which the self-organization (self-assembly) appears spontaneously on different scales. Their fundamental nature, have great importance in many fields including cosmology, nanophysics, materials science, and particle physics. Our research involves ferronematic based on both thermotropic and lyotropic liquid crystals doped with magnetic nanoparticles of various shapes. In our work, we concentrate on those self-organization processes and effects which are absent, or considerably modified in the absence of the magnetic nanoparticles.
(M. Molčan, M. Timko, P. Kopčanský, M. Kubovcikova)
Advanced functional materials exhibiting a great enhancement of the localized hyperthermia effect for cancer therapy applications are under intensive research. The present research focuses on the synthesis of such materials in the form of magnetite nanoparticles (NPs) and their nanocomposites showing tunable magnetic properties. Magnetic principles of heating mechanisms will be considered with respect to the optimum choice of nanoparticle preparation procedure, their size and size distribution, their magnetic and structural properties. Knowledge of the effect of particle properties with the harness of high specific heating power will provide necessary guidelines for development of nanoparticles tailored for potent hyperthermic effect and consecutively for various diseases treatment.
(L. Balejčíkov, P. Kopčanský, Z. Mitróová)
The preparation and characterization of magnetoferritin as synthetic derivate of ferritin – storage protein living organism. The aim of our activities is to develop new technologies of synthesis magnetic nanoparticles in magnetoferritin and establish magnetic, structural and morphological properties, size distribution and colloidal stability. As a results of this activity will be product with high potential in bio application area as targeting drug targeting, hyperthermia effect and MRI.
(M. Zentkova, Matúš Mihalik, M. Vavra, Marián Mihalik)
The project is focused on the manganite’s multiferroics (both orthorhombic and hexagonal) and selected hexaferrites, which are prepared as single crystals and nanoparticles. Crystal growth of single crystal enable us the study of magneto-crystalline anisotropy. We focus on Gd-, Dy- and Tb-based manganites and we pay attention to study of the substitution effect on magnetic and electric properties, heat capacity and lattice dynamic. The external parameters like high pressure and high magnetic field probe lattice dynamic, magnetic, transport and dielectric properties of prepared materials.
- MOLECULE BASED MAGNETS
(M. Zentkova, Matúš Mihalik, M. Vavra, Marián Mihalik)
The major aim of the project are comprehensive studies of selected magnetic materials. They are mainly cyanobridged molecular compounds of the 3d- or/and 4f-metals. We measure dynamic and static susceptibility and magnetization in the temperature range 2 – 300 K at ambient pressure and under pressure and in a commercial 3He probe enabling magnetic measurements in the temperature range of 0.5-2.0 K. As molecular compounds we study are always quite new and unexplored materials, it may be purposeful to do also other measurements, for example calorimetric, transport or spectroscopic.
(M. Zentkova, Matúš Mihalik, Marián Mihalik)
The main goal of the project is crystal growth of the Ce – Ni1-xCox – Ge,Si and U – Ni1-xCox – Ge,Si systems starting with Ni-based and Co-based parent compounds with stoichiometry 1:1:1, 1:1:2, 1:1:3 and 2:3:5 by arc melting and optical floating zone method. We study the formation of solid solutions. In generally the floating zone method is very suitable for crystal growth of solid solutions. Single crystals are required for study of magneto – crystalline anisotropy in the system and for study of superconductivity because single crystals are usually free of crystal defects which suppressed superconductivity.
- ELECTRICAL TRANSPORT AND TUNNELLING PHENOMENA
We study fundamental aspects of electrical transport in selected physical systems experimentally (by means of electrical resistivity and tunnelling spectroscopy studies), as well as theoretically. Currently our research is focused on theunderstanding the nature of electrical transport in the Kondo insulators SmB6 and YbB12, which were recently proposed as materials with possible existence of metallic topologically protected surface states. Present research activities include investigations of SmB6 thin films with the aim to evaluate the role of surface states in their electrical conduction. Our special goal is to verify applicability of the scenario of Kondo topological insulator and our model of valence-fluctuation induced hopping transport for description of electrical conduction of SmB6 thin films.
- ATOMIC FORCE MICROSCOPY
Studies of materials by Atomic Force Microscope (AFM) including advantageous AFM-based techniques, such as Magnetic Force Microscopy (MFM), Electric Force Microscopy (EFM), Kelvin Force Microscopy (KFM), and Piezo-response Force Microscopy (PFM), enable to determine local physical properties of materials down to nanometer scale. Our activity is devoted to the characterization of various materials such as amyloid fibriles, magnetozomes, nanotubes and magnetic nanoparticles, which are developed for purposes of perspective utilization in advantageous bio-applications. Also studies of domain structure of magnetically soft materials using MFM represent an important part of our research.
In general, our departmental research methodologies cover a broad spectrum of techniques and experimental approaches; employ state-of-the-art instrumentation for preparation and characterization of magnetic nanoparticles, magnetic fluids complex system containing magnetite nanoparticles –ferronematics, magnetoferritinandmagnetosome together with possibility their biomedical and technical application. Some research is devoted to study offundamental aspects of electrical transport in selected physical systems, cyanobridged molecular compounds and manganite’s multiferroics. For this purpose we can use Cryogen free system equipped by 18 Tesla magnet, TEM, hyperthermia system measurements and many others.
Thank you for your visit; explore our website and discover who we are and what we do.
Dr. Milan TIMKO
Head of Department