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Quantum materials are defined by the emergence of new properties resulting from collective quantum effects and by holding promise for their quantum applications. Novel superconductors, from high-Tc cuprates and iron-based superconductors to twisted monolayers, exhibit a higher level of emergent complexity, with a multiband electronic structure playing a pivotal role in their comprehension and potential applications. Here, we provide a brief overview of key multiband effects in these superconductors and topological semimetals, offering guidelines for the theory-assisted development of new quantum materials and devices.

The Fermi surface is related to the energy distribution of electrons in a solid, and governs physical properties of metals and semiconductors. A new type of angle-resolved photoemission spectroscopy, probing the Fermi surface and combining short recording time with high resolution, is now presented.

This review article summarizes recent progress in low-temperature properties of binary molybdenum-based alloys and intermetallic compounds, focusing mainly on superconductivity characteristics reflecting novel physics as well as possible applications. We present experimental data proving the two-band/two-gap nature of some superconducting compounds. As argued, the binary Mo–Re alloys with rhenium predominance represent an ideal and rare test system where related compounds with different Re/Mo ratios can be either centrosymmetrical or noncentrosymmetrical, leading in the latter case to possible mixed superconducting pairing. It is demonstrated that two MoC phases, namely, α-MoC and γ-MoC phases, are topologically nontrivial in their bulk and surface band structures, while amorphous MoSi and MoGe superconductors are among highly-promising materials for different superconductivity applications. We conclude the review with a brief discussion of new tendencies in computer modelling of the structure and properties of binary compounds, using as an example recently discovered stoichiometric MoBi2 compound, and practical prospects for already known and studied molybdenum-based superconductors.

The Josephson effect, as an example of a macroscopic quantum phenomenon, reveals itself in the three-layer heterostructures formed by two superconductors coupled by a weak link that usually consists of a 1–2 nm-thick insulating barrier. The traditional way of modelling such-systems’ dynamics is based on an equivalent circuit that comprises three parallel elements: a pure superconducting element with a certain supercurrent-versus-Josephson phase difference dependence, a resistor R, and a capacitor C. In this short review, we analyse the practical problem of reducing the junction capacitance while maintaining or slightly impairing other characteristics. Some arguments are presented to explain why the capacitance should be suppressed and how it will affect performance of superconducting quantum interference devices (SQUIDs) and digital electronics circuits. As a solution for low-capacitance junctions, we propose a weak link made of an amorphous-silicon interlayer doped with nanoscale metallic drops between the two superconducting Mo–Re-alloy electrodes.

Knowledge of a foreign language takes priority in modern conditions of globalization. Possession of integrated communication skills that ensure professional and business relationships between people of different countries becomes an obvious necessity for future foreign language specialists. Accordingly, the CLIL technique, known in the world and actively used for effective foreign language learning, is receiving special attention at the current stage. The article examines the main advantages and challenges of using the method of content and language integrated learning in the Ukrainian educational system, and draws attention to the main factors on which the successful implementation of the CLIL method in Ukraine depends. [ABSTRACT FROM AUTHOR]

The article analyses the issue of techniques of bilingual education by introducing CLIL comparing to ESP, EAP, EMI approaches at different levels of education – secondary and tertiary. In the article the authors studied the challenges, resilience and sustainability during the process of introduces above mentioned approaches. The CLIL approach facilitates foreign language learning by integrating language and content instruction. The authors’ investigation has a theoretical bias and different scientists’ point of view. By analyzing the implementation of CLIL approach and authors’ experience in practical application of other approaches the comparative analysis is done that proves the priorities of using CLIL at schools and higher educational establishments. The authors justified that CLIL is more than just language switching; it means that teaching subjects in a second language, like English, is the best way to make learning more meaningful and engaging. The benefits of CLIL in Ukrainian education system emphasize learners’ fluency in both languages - Ukrainian and English, high academic achievements, achievements in communication and development of sociocultural competencies that as a result boost learners’ motivation and bridge the language gap. [ABSTRACT FROM AUTHOR]

Methodology of content and language integrated learning (CLIL) is a gradual replacement of cramming and sometimes unconscious repetition. The principle of integration and functional contextual mastering of a foreign language have become extremely popular in the world, and have also made it possible to determine the advantages and problems of implementing the content and language integrated learning method into the educational process in many countries of the world. The given article is devoted to the issue of using the methodology of content and language integrated learning (CLIL) at each educational level of the Ukrainian education system, its methodological tasks are considered at each structural stage. Attention is paid to the main conditions for the successful implementation of the method of content and language integrated learning (CLIL) in Ukrainian secondary education institutions. The general principles of lesson planning and a series of English language lessons in Ukrainian secondary schools are considered. [ABSTRACT FROM AUTHOR]

The electronic structure of FeSe—the simplest iron-based superconductor (Fe-SC)—conceals a potential of abrupt increase of superconducting tran-sition temperature realized under the pressure or in a single-layer film. This is also a system where the appearing of a spontaneous electronic anisotropy known as the nematicity is formed far above the superconducting transition and is not accompanied with a magnetic ordering. The given review deals with the determining electronic structure of these compounds, its evolution with temperature, pressure, doping, and other impacts, which cause such key phenomena in Fe-SC as nematicity and high-temperature superconductivity.

Copyright of Progress in Physics of Metals / Uspehi Fiziki Metallov is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article issues the questions of effective teaching both content and second language by integrating CLIL and ESP within the process of professional competence formation at Ukrainian universities - the challenges, prerequisites and perspectives of teaching content and professionally oriented skills through the English language. The authors provide a comparative analysis of the definitions and characteristics of content and language integrated learning (CLIL) and English for specific purposes (ESP) at the present stage of linguodidactics. The investigation is theoretically granted and issues the question of CLIL and ESP integrated principles application, and reflects the main scientific ideas and stages of implementation, the application of which makes it possible to modernize the system of professional training according to European standards. Regarding the integration of the CLIL and ESP approaches in the process of professional training at nonlanguage specialties, the authors state that process of immersion into professional oriented environment facilitates the increase of learning outcome standards. Theoretical and methodological review of contemporary teaching approaches, its principles, advantages, challenges and effective ways of CLIL and ESP in Europe and Ukraine are analyzed. The usage of the methods of CLIL and ESP approaches are rational at different stages of professional education. [ABSTRACT FROM AUTHOR]

The article is devoted to the use of modern methods of the content and language integrated learning (CLIL), which allows a new approach to the issue of teaching school subjects. Thanks to this method, a teacher is able to demonstrate to students a close interdisciplinary connection, which can significantly affect the quality of education of students, their motivation to study, the development of interdisciplinary competences, skills and abilities. When using CLIL in English lessons and selecting exercises, the teacher should be guided by the basic principles of selecting educational material. Properly used educational material can be a great tool for students to learn new information. The article demonstrates the main advantages of the content and language integrated learning (CLIL) method, specifies the requirements for planning English language lessons, and gives examples of the types of tasks that can be used to form communication skills in students of primary and secondary schools of Ukraine. [ABSTRACT FROM AUTHOR]

The onset of superconductivity at the transition temperature is marked by the onset of order, which is characterized by an energy gap. Most models of the iron-based superconductors find a sign-changing (s±) order parameter [1–6], with the physical implication that pairing is driven by spin fluctuations. Recent work, however, has indicated that LiFeAs has a simple isotropic order parameter [7–9] and spin fluctuations are not necessary [7,10], contrary to the models [1–6]. The strength of the spin fluctuations has been controversial [11,12], meaning that the mechanism of superconductivity cannot as yet be determined. We report the momentum dependence of the superconducting energy gap, where we find an anisotropy that rules out coupling through spin fluctuations and the sign change. The results instead suggest that orbital fluctuations assisted by phonons [13,14] are the best explanation for superconductivity.

The article is devoted to the implementation of the method of content and language integrated learning (CLIL) in the process of teaching the discipline "Practical course of the English language" for students of the 2nd year of the specialty 014 Secondary education. Language and literature (English). Perfect knowledge of a foreign language has the greatest importance in today's globalization. Accordingly, special attention is paid at the present stage to the CLIL technique known in the world and actively used for effective foreign language learning. The purpose of the paper is to highlight the main advantages of using the CLIL methodology in teaching the students of the philological faculties of higher educational establishments of Ukraine. Here we give examples of tasks that can be used by teachers during students' study of the topic "Personality" for the purpose of assimilating vocabulary material, preparing students for discussion of the studied material and independent expression on the studied topic. The research emphasizes that the use of the CLIL methodology increases the motivation of students to learn English, promotes the development of their mental abilities, purposeful acquisition of lexical units, which will be used in their future professional activities. [ABSTRACT FROM AUTHOR]

The discovery of high-temperature superconductors (HTS) has led to understanding that, in order to explain and utilize the phenomenon, completely new physical approaches should be introduced at all scales: microscopic, mesoscopic, macroscopic. Leaving first two scales beyond the scope of the present paper, we focus in the upper limit of the last scale, the study of the magnetic flux dynamics in HTS bulks — the dynamics of the ‘compact vortex structures’. A new direction in the experimental superconducting physics, the investigation of HTS bulks with levitation techniques, which has been elaborated during last years to effectively explore the subject, as well as the new fundamental and applied results obtained there from are overviewed here.

The distribution of valence electrons in metals usually follows the symmetry of the underlying ionic lattice. Modulations of this distribution often occur when those electrons are not stable with respect [...]

The article is dedicated to the problem of content and language integrated learning (CLIL) in modern methodical and scientific literature of native and foreign scholars. The notion CLIL is explained, advantages of the presented methodology are pointed out. Special attention is paid to choosing the types of activities for teaching English the 1st year students at higher educational establishments of Ukraine which encourage studying a foreign language, help to develop creative mental abilities of learners, purposeful mastering of lexical units. The importance of the presented methodology and types of activities give opportunities learners to acquire knowledge in other subjects which they will use in their future professional activity. [ABSTRACT FROM AUTHOR]

The entry of fractional vortices and their subsequent dynamics inside a two-band superconductor is explored based on the numerical solutions of time-dependent Ginzburg–Landau (TDGL) equations. We consider the case when superfluid electron condensates from two zones are characterized by quite different parameters, such as coherence lengths ξi, and London penetration depths λi, which in turn leads to the different critical magnetic fields Hc,iand fractional flux quanta ϕivalues for the superconducting state in these two zones. Numerical solutions of TDGL equations in increasing external magnetic field followed by mathematical modeling of magnetic flux penetration were performed for this case by finite element method. We have explored the time evolution for the fractional vortices penetration process and their subsequent dynamics inside the specimens for two geometries: the circular disk, and the circular disk with a triangular cutout. Obtained results indicate that magnetic flux penetrates inside the specimen in the form of fractional vortices when they can overcome the edge barrier, which may be different for these two vortex types. Therefore, in increasing external magnetic field first penetrate vortices with a lower barrier height (i.e., lower Hc,i) while the other type of fractional vortices start their penetration at higher external field value. Another mechanism for the formation of fractional vortices during their entrance in a two-band superconductor is related to the difference in their flux values and viscosity coefficients which determine the rate of vortex proliferation inside the sample. Within the specimen, fractional vortices move in order to arrange. Vortices of different types attract to each other and try to stick together thus forming composite vortices with the whole flux quantum value ϕ0 = h/2e. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Physics of Metals / Uspehi Fiziki Metallov is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An observed correlation between the critical temperature of a superconducting transition in high-temperature superconductors and a proximity of their electronic structure to the topological Lifshitz transition needs to be verified on simple model materials. Here we show that such an object could be a Mo–Re alloy with an equal concentration of constituent elements. We present new evidence of the presence of two energy gaps in this material, obtained using point-contact spectroscopy, and argue that the studied Mo–Re alloy can be used for implementing new quantum effects associated with the phase difference of electron wave functions from the different bands. [ABSTRACT FROM AUTHOR]

In this article we are provided the temperature dependent angle-resolved photoemission spectroscopy (ARPES) study of different iron-based superconductors (FeSe, Fe(Se, Te), Ba(Co, Fe)As) in the vicinity of the superconducting transition. The existence of a strong downshift of the bands in the centre of the Brillouin zone (BZ) with temperature decrease is established for Fe(Se, Te). The value of such a shift for temperatures 4 K and 20 K is approximately 5 meV. Such changes are not observed for the dyz band of Ba(Co, Fe)2As2 and for the dxz band of FeSe. The observed strong dependence is likely to be the result of an interplay between the superconducting state and the mechanism that shifts bands in the temperature range from 20 to 300 K. [ABSTRACT FROM AUTHOR]

Copyright of Progress in Physics of Metals / Uspehi Fiziki Metallov is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)