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Ferromagnetic superconductor UCoGe is reported to be a week ferromagnet with Curie phase transition temperature $T_{\text{C}} \approx 2.5$ K. The magnetic order coexists with superconductivity that appears below critical temperature $T_{\text{SC}} \approx 0.7$ K. Nevertheless, the exotic coexistence of the mentioned physical phenomena is strongly sample dependent and only few samples can take pride in thereby. We have prepared a series of polycrystalline samples and single crystals using Czochralski and floating zone method. The samples were treated by a standard annealing under the vacuum or refined using solid state electrotransport. All samples were carefully characterized by X-ray and neutron diffraction methods and by electron-dispersive X-ray analysis in a scanning electron microscope. They were subsequently also studied with respect to magnetism and superconductivity by electrical resistivity, magnetization, AC susceptibility and specific heat measurements. The results have been analyzed and the relations between the sample quality, ferromagnetism and superconductivity are discussed.

Nanoparticles serving as a multifunctional and multiaddressable dopant to modify the properties of liquid crystalline matrices are developed by combining cobalt ferrite nanocrystals with organic ligands featuring a robust photosensitive unit and a source of chirality from the natural pool. These nanoparticles provide a stable nanocomposite when dispersed in achiral liquid crystals, giving rise to chiral supramolecular structures that can respond to UV-light illumination, and, at the same time, the formed nanocomposite possesses strong magnetic response. We report on a nanocomposite that shows three additional functionalities (chirality and responsiveness to UV light and magnetic field) upon the introduction of a single dopant into achiral liquid crystals.