Twist-tunable moir\'e optical resonances

Multilayer stacks of twisted optical metasurfaces are considered as a prospective platform for chiral nanophotonic devices. Such structures are primarily used for the realization of circularly polarized light sources, artificial optical rotation, and circular dichroism. At the same time, the behavior of their hybrid photonic modes is strongly affected by the moir\'e-pattern of superimposed periodic constituents. In this work, we show that moir\'e-periodicity in bilayer dielectric photonic crystal slabs leads to an arise of unlimitedly narrow optical resonances, which are very sensitive to the relative twist and gap width between the sublayers. We demonstrate the structure providing twist-tuning of the hybrid mode wavelength in the range of 300--600~nm with quality factor varying from~$10^2$~up~to~$10^5$ correspondingly. The obtained results pave the wave for the utilization of moir\'e-assisted effects in multilayer photonic crystal slabs

Chiral light in twisted Fabry-P\'erot cavities

Fundamental studies of the interaction of chiral light with chiral matter are important for the development of techniques that allow handedness-selective optical detection of chiral organic molecules. One approach to achieve this goal is the creation of a Fabry-P\'erot cavity that supports eigenmodes with a desired electromagnetic handedness, which interacts differently with left and right molecular enantiomers. In this paper, we theoretically study chiral Fabry-P\'erot cavities with mirrors comprising one-dimensional photonic crystal slabs made of van der Waals As$_2$S$_3$, a material with one of the highest known in-plane anisotropy. By utilizing the anisotropy degree of freedom provided by As$_2$S$_3$, we design Fabry-P\'erot cavities with constitutional and configurational geometrical chiralities. We demonstrate that in cavities with constitutional chirality, electromagnetic modes of left or right handedness exist due to the chirality of both mirrors, often referred to as handedness preserving mirrors in the literature. At the same time, cavities with configurational chirality support modes of both handednesses due to chiral morphology of the entire structure, set by the twist angle between the optical axes of the upper and lower non-chiral anisotropic mirrors. The developed chiral Fabry-P\'erot cavities can be tuned to the technologically available distance between the mirrors by properly twisting them, making such systems a prospective platform for the coupling of chiral light with chiral matter.Comment: 33 pages, 9 figure

The Problem of Law-Abiding Behavior among Minors in Educational Institutions: Domestic and Foreign Experience

At present, the problem of sustaining the law-abiding behavior of minors in educational institutions, identifying and eliminating the causes and conditions that contribute to the development of deviant behavior of students is becoming more and more topical. This paper presents the results of a monitoring study of the current state of the activities carried out by educational institutions to form the law-abiding behavior of minors in the territorial entities of the Russian Federation. It also presents the results of a theoretical study of the foreign experience of educational institutions in the framework of maintaining the law-abiding behavior of minors in the educational environment. The conclusions have been drawn that a system-activity approach should be the basis of an educational impact in educational institutions which will provide: the formation of students’ readiness for self-development; the design and construction of a social environment for the development of students based on moral principles, traditional Russian values, relevant scientific knowledge and skills, respect for the traditions of the multinational, multicultural and multiconfessional Russian society; active educational and cognitive activities of students; building educational and moral education activity, taking account of the individual age-related psychological and physiological characteristics of students and with a focus on educational results. The materials of the paper are part of a large-scale study within the framework of the "Conception for the development of a system for the prevention of neglect and juvenile delinquency for the period up to 2020", conducted by a team of scientists from 2017 to 2020, whose scientific interests lie in the study of the problem of deviant behavior of minors

Adaptive capacity for climate change: Local initiatives and federal planning. The case of Tiksi, Sakha Republic, Russia

International audienceClimate change exacerbates existing threats and risks and generates new ones in the lives of the Indigenous people of the Arctic regions. The ability to cope with climate variability and extreme events is largely dependent on territorial adaptive capacities and vulnerabilities in addition to the level of regional economic development. The purpose of this article is to understand if the people living in Tiksi and its hinterland are aware of the impacts of climate change and attribute importance to them, as well as to determine if they have adaptation actions and strategies have been put in place. The future of Tiksi's population is uncertain and is highly dependent on the federal government. Issues relating to climate change are not a high priority for the local populations. Although the population of the Bulunsky district has maintained some capacity for adaptation, both uncertainty about the future and their dependence on decisions made at a higher level are undermining their ability to plan for adaptation in the long term

The Problem of Law-Abiding Behavior among Minors in Educational Institutions: Domestic and Foreign Experience

At present, the problem of sustaining the law-abiding behavior of minors in educational institutions, identifying and eliminating the causes and conditions that contribute to the development of deviant behavior of students is becoming more and more topical. This paper presents the results of a monitoring study of the current state of the activities carried out by educational institutions to form the law-abiding behavior of minors in the territorial entities of the Russian Federation. It also presents the results of a theoretical study of the foreign experience of educational institutions in the framework of maintaining the law-abiding behavior of minors in the educational environment. The conclusions have been drawn that a system-activity approach should be the basis of an educational impact in educational institutions which will provide: the formation of students’ readiness for self-development; the design and construction of a social environment for the development of students based on moral principles, traditional Russian values, relevant scientific knowledge and skills, respect for the traditions of the multinational, multicultural and multiconfessional Russian society; active educational and cognitive activities of students; building educational and moral education activity, taking account of the individual age-related psychological and physiological characteristics of students and with a focus on educational results. The materials of the paper are part of a large-scale study within the framework of the "Conception for the development of a system for the prevention of neglect and juvenile delinquency for the period up to 2020", conducted by a team of scientists from 2017 to 2020, whose scientific interests lie in the study of the problem of deviant behavior of minors.En la actualidad, el problema de sustentar la conducta respetuosa de la ley de los menores en las instituciones educativas, identificando y eliminando las causas y condiciones que contribuyen al desarrollo de conductas desviadas de los estudiantes se está volviendo cada vez más actual. Este artículo presenta los resultados de un estudio de seguimiento del estado actual de las actividades que realizan las instituciones educativas para formar el comportamiento respetuoso de la ley de los menores en las entidades territoriales de la Federación de Rusia. También presenta los resultados de un estudio teórico de la experiencia extranjera de las instituciones educativas en el marco del mantenimiento del comportamiento respetuoso de la ley de los menores en el ámbito educativo. Se ha extraído la conclusión de que un enfoque de actividad sistémica debe ser la base de un impacto educativo en las instituciones educativas que proporcione: la formación de la preparación de los estudiantes para el autodesarrollo; el diseño y la construcción de un entorno social para el desarrollo de los estudiantes basado en principios morales, valores tradicionales rusos, conocimientos y habilidades científicas relevantes, respeto por las tradiciones de la sociedad rusa multinacional, multicultural y multiconfesional; actividades educativas y cognitivas activas de los estudiantes; Construir una actividad educativa y de educación moral, teniendo en cuenta las características psicológicas y fisiológicas de los estudiantes relacionadas con la edad y con un enfoque en los resultados educativos. Los materiales del trabajo forman parte de un estudio a gran escala en el marco de la "Concepción para el desarrollo de un sistema para la prevención del abandono y la delincuencia juvenil para el período hasta 2020", realizado por un equipo de científicos desde 2017 al 2020, cuyos intereses científicos radican en el estudio del problema del comportamiento desviado de los menore

Chiral light in twisted Fabry-P\'erot cavities

Fundamental studies of the interaction of chiral light with chiral matter are important for the development of techniques that allow handedness-selective optical detection of chiral organic molecules. One approach to achieve this goal is the creation of a Fabry-P\'erot cavity that supports eigenmodes with a desired electromagnetic handedness, which interacts differently with left and right molecular enantiomers. In this paper, we theoretically study chiral Fabry-P\'erot cavities with mirrors comprising one-dimensional photonic crystal slabs made of van der Waals As$_2$S$_3$, a material with one of the highest known in-plane anisotropy. By utilizing the anisotropy degree of freedom provided by As$_2$S$_3$, we design Fabry-P\'erot cavities with constitutional and configurational geometrical chiralities. We demonstrate that in cavities with constitutional chirality, electromagnetic modes of left or right handedness exist due to the chirality of both mirrors, often referred to as handedness preserving mirrors in the literature. At the same time, cavities with configurational chirality support modes of both handednesses due to chiral morphology of the entire structure, set by the twist angle between the optical axes of the upper and lower non-chiral anisotropic mirrors. The developed chiral Fabry-P\'erot cavities can be tuned to the technologically available distance between the mirrors by properly twisting them, making such systems a prospective platform for the coupling of chiral light with chiral matter