Conveners
Poster session + káva: prezentácie vedeckých výsledkov FMFI UK Zamestnanci Fyzika
- Peter Cermak (KEF FMFI UK, Bratislava)
- Robert Breier (Comenius university, Bratislava (SK))
Titanium dioxide nanotubes are promising nanomaterials with wide-range potential applications in energy, environmental, and medical fields, driven by their tunable structure and exceptional properties. However, pure TiO2 nanotubes usage is limited by relatively wide energy gap.
The fabrication and oxidation processes of iron-doped titanium nanotubes were investigated. The structural and...
Indoor air can be polluted by many different harmful contaminants, such as chemicals, viruses or bacteria, aerosols or fine particles from combustion, among others [1]. The recent global pandemic is the perfect example showing how contaminants such as viruses are dealt with. Instead of destroying or inactivating them, physical barriers, i.e. filters, were mostly used. Similarly, current...
Coumarin is widely used in cosmetics and pharmaceuticals, has emerged as a persistent and potentially toxic contaminant. This study investigates coumarin degradation using a modified fountain dielectric barrier discharge (MF-DBD) plasma reactor, operated alone and in combination with WO₃, WO₃–ZnO, and ZnO catalysts. Under identical conditions (16 mg/L, atmospheric air pressure, 0–65 min),...
The four-terminal measurement technique is a foundational and widely utilized method for determining the electrical conducting characteristics of materials, especially thin films, bulk crystals, semiconductors, and complex nanostructures. By employing four separate electrical contacts - two for current injection and two for voltage measurements - on top of a sample, this methodology...
We present a bottom-up approach to an effective theory that simultaneously explains the matter–antimatter asymmetry via leptogenesis, the dark matter relic abundance via freeze-in or freeze-out mechanisms, and neutrino masses via the Weinberg operator. We show that, in the minimal scenario, only two new particles and a single portal operator coupling the visible and dark sectors are sufficient...
OSCAR (One-Station methods for site ChARacterisation) is an international, collaborative benchmark that compares single-station approaches—i.e., methods using a single three-component seismometer—for estimating subsurface structure. Its goal is to provide the missing standardized framework for comparing these increasingly popular methods, which offer low cost and simple logistics at the...
The ISOLDE facility at CERN is one of the world’s leading centers for the investigation of exotic nuclei and their structure. Thanks to large production yields and element-selective laser ionisation, ISOLDE provides access to a broad range of radioactive isotopes far from stability. Various experimental techniques, for example, laser or decay spectroscopy, are used to probe properties of these...
KM3NeT collaboration announced an observation of the most energetic cosmic neutrino with energy of 220 PeV on Wednesday, February 12, 2025, by means of a publication in Nature journal. This event, practically near-horizontal muon traversing three-dimensional network of optical modules (photosensors) of the telescope, was registered by the ARCA detector that is located offshore Sicily at a...
Cold plasma discharges generate reactive oxygen and nitrogen species (RONS), which can be trapped in the liquid phase to form plasma-activated water (PAW), a chemically rich solution with applications in agriculture, biomedicine, and environmental treatment. When transient spark (TS) discharges are coupled with electrospray (ES) microdroplet generation, PAW production efficiency increases...
Direct injection of electrons into synthetic bone mineral hydroxyapatite can change its surface potential in thin films prepared by spin coating, reduce bacterial adhesion at the surface of bulk ceramics and impact biological adhesion. To explore this further, we investigate direct electron injection, and trapping of charge in hydroxyapatite thin films produced by Pulsed Laser Deposition (PLD)...
Topological phases emerge from the global properties of electronic band structures, stabilized by time-reversal or mirror symmetries. Their hallmark is the presence of gapless boundary states that are robust against perturbations and enable charge transport without backscattering. To realize a non-trivial conducting state, we adopted a stacking strategy by fabricating a superlattice composed...
Transition metal borides (TMBy) represent a structurally rich group of materials with attractive physical properties, including high hardness and high melting points, making them promising candidates for applications in extreme conditions. Considerable attention has been paid to overstoichiometric TMB2+Δ films with hexagonal α-P6/mmm structure exhibiting super-hardness attributed to high...
We study spaces that don’t have to be continuous like ordinary space but can instead be built from matrices that replace the usual notion of points. These matrix spaces allow us to explore what happens when geometry itself becomes quantum. Our work includes well-known examples such as the fuzzy sphere and newer constructions like the fuzzy onion, where several fuzzy layers form a richer...
Current demands on computing technologies and storage units, such as speed, low power consumption, and high memory density, are leading to the development of new technologies. One promising area is superconducting cryoelectronics, including qubits, superconducting spintronics, or memory cells. Devices combining two antagonistic phenomena – superconductivity and ferromagnetism – show great...
Cold atmospheric plasma generates multiple reactive oxygen and nitrogen species (RONS), which dissolve in water to form plasma-activated water (PAW), resulting in its subsequent chemical modifications. Due to the presence of RONS, PAW shows considerable potential in agriculture, as these species act as signaling molecules in plant metabolic pathways and enhance nutrient availability. This...
Beryllium-10 ($^{10}$Be) is a long-lived radioactive cosmogenic isotope of beryllium (half-life = 1.387 Ma), primarily produced in the Earth’s atmosphere through spallation reactions induced by high-energy cosmic rays. Owing to its extended half-life and β⁻-decay mode, the quantification of $^{10}$Be at ultratrace levels in natural samples is most effectively achieved using accelerator mass...
Most objects in space are too distant to be studied in situ. Therefore, emission spectroscopy is one of the primary methods used. The generation of excited species responsible for this emission can be induced either by radiation from nearby stars or by collisions with other particles. In our Solar System, planets and small bodies are constantly exposed to photon irradiation from the Sun. These...
Thin-film systems exhibiting magnetoresistive effects have found broad practical application in various industries, including nanoelectronics, automotive engineering, and biotechnology. During the operation of devices that utilize magnetoresistive elements (e.g., non-volatile magnetic memory such as MRAM, or magnetic field sensors), the materials are subjected to elevated temperatures. The...
This work is devoted to development and characterization of inter-electrode separators for alkaline water electrolysis (WE) for hydrogen production. The purpose of the separator is to prevent mixing of the produced hydrogen and oxygen, therefore the separator must possess low permeability to these gases under WE conditions. Meanwhile, the separator must be highly conductive to OH- ions to...
The versatility and design adaptability of the Spatial Heterodyne Spectrometer (SHS) have proven to be beneficial in various disciplines, including analyses in atmospheric, astrophysical, elemental, and others [1]. A hybrid of interferometric and dispersive domains of the spectrometers is implemented in the single SHS spectrometer, providing high throughput and resolutions with design...
Silver-containing nanocomposite coatings were deposited using the High Target Utilization Sputtering technique (HiTUS) by simultaneous sputtering of Ag target and polymerization of hexamethyldisiloxane (HMDSO) vapours in the radiofrequency plasma. The presence of silver in the form of nanoclusters with dimensions below 10 nm embedded in an amorphous organosilicon plasma polymer was confirmed...
The term "superconducting diode effect" (SDE) was introduced in the context of advancing superconducting quantum electronics. However, the ac rectification was observed in the 1960s in dc SQUIDs caused by asymmetry in their current–voltage characteristics in magnetic fields. Later, similar behavior was identified in wide thin films due to asymmetry in the Bean–Livingston edge...
In our laboratory, we study the interaction of light with small molecules (such as ammonia or NOx radicals). These particles often play a key role in everyday physical and chemical processes on both terrestrial and cosmic scales. One example is the characterization of exoplanets based on the detection of such molecules in their atmospheres.
Effective analysis of absorption signals requires a...
Modern experimental techniques, such as Accelerator Mass Spectrometry (AMS), allow us to analyze environmental samples with high sensitivity and resolution. The concentration of cosmogenic nuclides in these samples is the result of the interplay between three processes: production, transport, and deposition. The knowledge of involved processes and their simulations allowed us to obtain...
This study investigates laser ablation of materials relevant for thermonuclear reactor walls under various laser irradiation conditions. Copper was selected as the target material due to its high thermal and electrical conductivity and relevance in fusion technology. The study is focused on laser ablation processes using a EKSPLA NT342C laser system operating at a wavelength of 532 nm with...
On Monday, October 9, 2023, 20:23 CEST, an earthquake with a local magnitude of 4.9 occurred in Eastern Slovakia with an epicenter near the village of Ďapalovce. The epicentral macroseismic intensity reached 8° EMS-98. It was the strongest earthquake on the territory of Slovakia in more than 100 years (since earthquake on the night of January 9-10, 1906 near the municipality Dobrá Voda,...
Traveling-Wave Parametric Amplifiers (TWPAs) are essential tools for ultra-sensitive measurements, particularly in quantum systems. Their performance, however, is often limited by challenges in impedance and phase matching. Conventional phase-matching techniques, such as periodic impedance modulation or the use of resonators and phase shifters, complicate circuit design and increase impedance...
Volatile organic compounds (VOCs) such as toluene are major air pollutants, contributing to photochemical smog and posing severe environmental and health risks. Conventional abatement methods often require high operating temperatures or show poor efficiency for intermittent emissions. In this study, non-thermal plasma (NTP) assisted VOC decomposition was investigated using a dielectric barrier...
