Electric field induced strong localization of electrons on solid hydrogen surface: possible applications to quantum computing

Two-dimensional electron system on the liquid helium surface is one of the leading candidates for constructing large analog quantum computers (P.M. Platzman and M.I. Dykman, Science 284, 1967 (1999)). Similar electron systems on the surfaces of solid hydrogen or solid neon may have some important advantages with respect to electrons on liquid helium in quantum computing applications, such as larger state separation $\Delta E$, absence of propagating capillary waves (or ripplons), smaller vapor pressure, etc. As a result, it may operate at higher temperatures. Surface roughness is the main hurdle to overcome in building a realistic quantum computer using these states. Electric field induced strong localization of surface electrons is shown to be a convenient tool to characterize surface roughness.Comment: 4 pages, 3 figure

Development of human capital in the system of economic categories of work

Today, human capital is one of the main factors in the formation of the knowledge economy, which is the highest stage in the development of an innovative, post-industrial economy. The development of intellectual and spiritual capabilities of a person, as well as the accumulation of human capital, which has a strong influence on the productivity and quality of labor, becomes one of the priorities for the future development of the state. This article discusses the development of human capital in the system of economic categories of labor.peer-reviewe

Nonlinear two-level dynamics of quantum time crystals

A time crystal is a macroscopic quantum system in periodic motion in its ground state. In our experiments, two coupled time crystals consisting of spin-wave quasiparticles (magnons) form a macroscopic two-level system. The two levels evolve in time as determined intrinsically by a nonlinear feedback, allowing us to construct spontaneous two-level dynamics. In the course of a level crossing, magnons move from the ground level to the excited level driven by the Landau-Zener effect, combined with Rabi population oscillations. We demonstrate that magnon time crystals allow access to every aspect and detail of quantum-coherent interactions in a single run of the experiment. Our work opens an outlook for the detection of surface-bound Majorana fermions in the underlying superfluid system, and invites technological exploitation of coherent magnon phenomena – potentially even at room temperature

Discrete Family of Dissipative Soliton Pairs in Mode-Locked Fiber Lasers

We numerically investigate the formation of soliton pairs (bound states) in mode-locked fiber ring lasers. In the distributed model (complex cubic-quintic Ginzburg-Landau equation) we observe a discrete family of soliton pairs with equidistantly increasing peak separation. This family was identified by two alternative numerical schemes and the bound state instability was disclosed by a linear stability analysis. Moreover, similar families of unstable bound state solutions have been found in a more realistic lumped laser model with an idealized saturable absorber (instantaneous response). We show that a stabilization of these bound states can be achieved when the finite relaxation time of the saturable absorber is taken into account. The domain of stability can be controlled by varying this relaxation time

A Model of Fuel and Energy Sector Contribution to Economic Growth

The study examined the impact of foreign direct investment (FDI) in the fuel and energy sector and related industries on economic growth in response to the debates on FDI's impact on economic growth being positive (government officials and policymakers) or negative (the World Bank, some researchers). The hypothesis that a significant relationship is present between the Russian Federation GDP and gross FDI in Fuel and Energy Sector (fuels and non-fuels fossils mining, coke and petrochemicals production, rubber and plastic production, and energy supply) is introduced and validated by using a regression model. The derived model tests changes of regression results patterns of the Russian GDP against FDI in energy-related industries in different periods 1998-2004 and 2010-2017. GDP is assessed in five different measures: current US dollars, international US dollars (purchasing power parity), growth rates of the former and the latter, and physical growth index. It was concluded that, to a greater extent, economic growth is influenced by foreign investment in energy supply and petrochemical production in the both periods. Increased investment in power generation also contributes to economic growth, while other constituents of the sector, including mining, have a statistically insignificant or even retarding effect on economic growth, thus evidencing in favor of the World Bank's criticism towards FDI. Policy implications of the findings prove the necessity to introduce structural changes intended to redirect capital flows from oil and gas to prevent from economic growth deterioration in the long-term perspective. Keywords: Economic growth; Foreign Direct Investment; Fuel and energy sector JEL Classifications: C3, O4, Q43 DOI: https://doi.org/10.32479/ijeep.784

Water-repellent coatings for surface and 3D wood processing

The paper presents the results of research in organic chemical compositions for hydrophobic protection of wood with the use of surface and three-dimensional coating techniques of impregnation and chemical compositions. Water absorption indicators, angles of contact on the surface of treated samples are detected herein. Kinetic equation of the moisture diffusion transition in capillary-porous structure of wood is suggested

Possibilities of transcranial direct current stimulation (tDCS) use in elite sport

Transcranial direct current stimulation has proven to be the method that can modulate neural activity in various cases. As this method has been shown to be effective in improving muscular strength, reaction time and accuracy, motor learning, it seems to be promising in elite sports.This paper provides an overview of studies on tDCS and its impact on central nervous system functioning, with an emphasis on potential sports utility. This review demonstrates that the basic mechanism of the effect of tDCS on nervous system functioning is its ability to modulate the excitability of neurons.tDCS is able to influence various components of electrocortical potentials, the amplitude of the motor evoked potential, as well as the mechanisms of long-term potentiation and, as a consequence, the cellular mechanisms of motor learning and neuroplasticity in general. The beneficial effect of tDCS on attention selectivity and signal detection has been noted. It is also shown that tDCS can accelerate learning and enhance performance in a range of complex cognitive tasks.In addition, a number of studies showing that tDCS can increase the efficiency of performing arithmetic and problem solving tasks are considered.In the context of sports, the influence of tDCS over motor areas on motor learning and on the accuracy of voluntary movements seems to be important. Its ability to influence speed and strength indicators, namely, the maximum isometric force of various muscle groups and explosive strength, as well as endurance indicators seems promising, too. The review also shows that tDCS is reasonably safe and that serious adverse effects are extremely rare; the most common adverse effect is local skin irritation due to poor electrode placement

An Integrated Approach to Measuring Emissions from Confined Animal Feeding Operations at the Whole Facility Scale

Agricultural operations produce a variety of particulates and gases that influence air quality. Agriculture, through wind erosion, tillage and harvest operations, burning, diesel-powered machinery and animal production operations, is a source of particulate matter that can enter human lungs and cause pulmonary problems. Animal production operations can be a source of gaseous emissions such as ammonia, odor-causing volatile organic compounds, hydrogen sulfide, greenhouse gases (methane, nitrous oxides) and airborne pathogens. These emissions can negatively impact human health, property values, and the environment. The presence of buildings and other structures often make whole facility measurement capability a requirement for understanding the source strength and characteristics. The ability to use standoff methods to determine the movement and concentrations of emissions on a whole facility basis opens new capabilities for model development and verification. An integrated system to measure whole facility emission was designed to characterize the complex structures and temporally dependent emission rates often associated with production operations. This approach combines state of the art standoff measurement techniques with standard point source monitoring equipment to provide the calibrated, high spatial and temporal frequency data required to develop and validate the models required for emission reduction and regulation. This effort includes the design, construction and operation of a new multi-wavelength lidar developed to map and track particle emissions. The lidar incorporates a laser emitting simultaneous, pulsed NdYAG laser radiation at 355, 532 and 1064 nm at a pulse frequency of 10 kHz. The system also includes open path FTS measurements for integrated chemical concentrations, and state-of-the-art point measurements of turbulence, particulate and gas concentrations. This approach was evaluated in a multidisciplinary atmospheric study at a swine production farm in Iowa. Aerosol plumes emitted from the facility were prominent phenomena, and their variations with temperature, turbulence, stability and feed cycle were studied, using arrays of particle samplers and turbulence detectors. Other lidar measurements focused on air motion as seen by long duration scans of the farm region. Successful operation of this system confirms the value of the multidimensional approach for the determination of agricultural emissions in the complex terrain often accompanying production facilities

Search for directional associations between Baikal Gigaton Volume Detector neutrino-induced cascades and high-energy astrophysical sources

Baikal-GVD has recently published its first measurement of the diffuse astrophysical neutrino flux, performed using high-energy cascade-like events. We further explore the Baikal-GVD cascade dataset collected in 2018-2022, with the aim to identify possible associations between the Baikal-GVD neutrinos and known astrophysical sources. We leverage the relatively high angular resolution of the Baikal-GVD neutrino telescope (2-3 deg.), made possible by the use of liquid water as the detection medium, enabling the study of astrophysical point sources even with cascade events. We estimate the telescope's sensitivity in the cascade channel for high-energy astrophysical sources and refine our analysis prescriptions using Monte-Carlo simulations. We primarily focus on cascades with energies exceeding 100 TeV, which we employ to search for correlation with radio-bright blazars. Although the currently limited neutrino sample size provides no statistically significant effects, our analysis suggests a number of possible associations with both extragalactic and Galactic sources. Specifically, we present an analysis of an observed triplet of neutrino candidate events in the Galactic plane, focusing on its potential connection with certain Galactic sources, and discuss the coincidence of cascades with several bright and flaring blazars.Comment: 10 pages, 3 figure