Fyzikální ústav

Nejnovější přírůstky:
2023-11-19
00:04
Technological challenges in the fabrication of MoS.sub.2./sub./diamond heterostructures
Varga, Marián ; Sojková, M. ; Hrdá, J. ; Hutar, P. ; Parsa Saeb, S. ; Vanko, G. ; Pribusova Slusna, L. ; Ondič, Lukáš ; Fait, Jan ; Kromka, Alexander ; Hulman, M.
Nowadays, 2D materials are one of the most studied classes of materials. In addition to the most famous graphene, progress has been achieved in studying and using fundamental properties of transition metal dichalcogenides (TMD). Complementary, diamond as a representative of 3D materials has gained a reputation as an extremely versatile material due to its extraordinary combination of physical/chemical/electrical/optical properties. Besides these particular forms of 2D and 3D materials, their heterostructures have become very attractive due to new phenomena and functions (bandgap engineering, enhanced charge transport, optical interaction, etc.). However, individual technological procedures are still minimally investigated and described. Here, we will demonstrate a proof-of-concept for the preparation of MoS2/diamond heterostructures, where two different strategies were employed: a) growth of MoS2 layers on diamond films, and b) growth of diamond films on Si/MoS2 substrates.

Úplný záznam
2023-10-16
21:27
Book of Abstracts of the 32st Joint Seminar Development of Materials Science in Research and Education (DMSRE)
Kožíšek, Zdeněk ; Král, Robert ; Zemenová, Petra
Conference topics. Trends in the development of materials research. Information about the research programs of individual institutions. Results of materials research. Education of materials science at the universities. Information about equipment for preparation and characterization of materials.\n

Úplný záznam
2023-10-16
21:27
Book of abstracts of the 1st outdoor seminar of the Department of Optical Materials: Advances in the new materials engineering and study
Buryi, Maksym ; Král, Robert
The seminar is dedicated to the main activities of the department of Optical Materials, FZU - Institute of Physics of the Czech Academy of Sciences in the course of national and international collaborations. In particular, the advanced methods of the (nano)materials synthesis, fabrication, and characterization are presented and discussed in detail. The aim of the seminar is to establish more of the effective paths of communication and data exchange by creating and maintaining links among the teams of national and international experts in various fields of physical and chemical knowledge, both experimental and theoretical.

Úplný záznam
2023-06-04
00:44
Room temperature ethanol detection using carbon materials
Kočí, Michal
Allotropic forms of carbon, in particular graphene oxide (GO) or nanocrystalline diamond (NCD), attracted the attention of many research groups due to their unique electronic structures and extraordinary physical and chemical properties, preferable for many different applications, including sensor devices. This work focuses on responses of various sensing layers (NCD with hydrogen termination (H-NCD), graphene oxide (GO), reduced graphene oxide (rGO), thiol-functionalized graphene oxide (GO-SH) and their hybrid structures to ethanol vapor with concentrations up to 100 ppm in synthetic air at room temperature. The measured parameters of the tested sensors, especially stability, reproducibility and regeneration, are compared and critically evaluated. The high sensitivity of tested sensors achieved at room temperature makes them very promising for monitoring ethanol vapor as well as other volatile substances (e.g., isopropyl-alcohol or acetone).

Úplný záznam
2023-04-09
00:00
Enhanced growth rate of diamond films at low temperature in focused microwave plasma system
Babčenko, Oleg ; Bydžovská, Irena ; Fait, Jan ; Shagieva, Ekaterina ; Ondič, Lukáš ; Kromka, Alexander
The low temperature (< 500 °C) diamond film deposition on fused silica in two different focused microwave plasma systems, i.e. a multimode clamshell cavity (MCC) and a rotational ellipsoid cavity (REC) reactor, was investigated. During the experiments, the methane to hydrogen ratio, in the hydrogen-rich process gas mixture, varied from 1 % to 15 % for MCC and from 1 % to 9 % for REC. The grown films were analyzed by scanning electron microscopy and Raman shift measurements. The outcomes of the study and enhanced diamond growth at low temperatures is advantageous for overcoating of fused silica as well as thermally sensitive substrates, e.g. optical elements, photonic crystals, sensors, etc.

Úplný záznam
2023-03-12
00:04
CERTIFIKOVANÁ METODIKA, Metodika pro maloobjemovou sterilizaci násadových vajec
Bezděk, D. ; Dejneka, Alexandr ; Kubinová, Šárka ; Fejt, T. ; Churpita, Olexandr ; Drahošová, Michala
Metodika je výsledkem řešení výzkumného projektu č. TH04030206 s názvem: Výzkum využití fyzikálních metod sterilizace vajec pro líhnění. Cílem projektu je rozvoj fyzikálních metod sterilizace násadových vajec - zejm. rozvoj metody nízkoteplotního plazmatu (NTP). Metoda NTP je nasazena se záměrem zvýšit efektivitu drůbežího chovu a výrazně snížit zdravotní a ekologickou zátěž. Zvýšením přidané hodnoty a efektivity chovu dále projekt přispívá ke konkurenceschopnosti drůbežářského průmyslu a tím i k potravinové soběstačnosti ČR.

Úplný záznam
2023-01-29
22:31
Tenké vrstvy pro fotovoltaiku nanášené plasmochemickými metodami
Fejfar, Antonín
Tenké vrstvy jsou klíčovou komponentou prakticky všech moderních fotovoltaických článků pro využití sluneční energie. Články využívají tenké vrstvy pro dosažení optimálního záchytu světla, pro rozdělení a sběr fotogenerovaných nábojů i pro pasivaci rozhraní či přímo jako vrstvy absorbující fotony slunečního svitu. Každoročně jsou tak nanášeny vrstvy o celkové ploše řádu mnoha stovek kilometrů čtverečních, a to především s využitím plazmochemických technologií.

Úplný záznam
2023-01-08
22:31
Magnetocrystalline anisotropy of Ni-Mn-Ga-Co-Cu martensite
Rameš, Michal ; Straka, Ladislav ; Sozinov, A. ; Heczko, Oleg
The martensites of Heusler alloys based on Ni-Mn-Ga exhibit magnetically-induced reorientation resulting in giant field-induced strain. Up to 12% strain was observed in Ni-Mn-Ga-Co-Cu with 4 at.% of Co and Cu. The driving force of the phenomenon is the magnetocrystalline anisotropy. We studied evolution of the anisotropy with temperature and compositions using magnetiyation curve measurements in four different single crystalline Ni-Mn-Ga-Co-Cu and compared with non-doped Ni-Mn-Ga. The anisotropy of martensite decreases with increasing average doping (Co+Cu)/2 but it does not scale with tetragonal ratio or valence electron concentration.

Úplný záznam
2023-01-08
22:31
Effect of molecular structure on liquid crystalline behaviour for chiral lactic acid derivatives
Mironov, Sergei ; Bubnov, Alexej
Liquid crystals are self-organizing materials that have great potential for practical applications. The relationship <molecular structure - mesomorphic properties> has not been fully established and understood despite numerous studies. We discuss a relatively broad subclass of calamitic chiral lactic acid derivatives and provide specific examples of effective tuning of their mesomorphic and electro-optical behaviour using various types of lateral substitution placed on the molecular core.

Úplný záznam
2022-12-11
22:31
Vliv velikosti zrn práškového NaCl na jeho termické vlastnosti
Falvey, Alexandra ; Zemenová, Petra ; Vaněček, Vojtěch ; Bystřický, Aleš ; Stehlík, Štěpán ; Král, Robert
Příspěvek se zabývá studiem tepelného chování vzorku NaCl v práškové formě (s homogenní a nehomogenní distribucí zrn, různou vlhkostí) a monokrystalického NaCl metodami termické analýzy (DSC a TMA) a hmotnostní spektrometrii (MS).

Úplný záznam