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We investigated an optical microsensor of the polarization state of a laser light based on a metalens. In contrast to known polarization sensors based on metasurfaces that deflect different polarization types using various angles to the optical axis, the studied polarization sensor generated different patterns in the metalens focus to realize varied polarization states: left circular polarization generated a light ring in the focus, right circular polarization generated a circular focal spot, and linear polarization generated an elliptic spot with two sidelobes. Moreover, the tilt angle of the linear polarization matched the tilt angle of the elliptic focal spot. The simulation results were consistent with the theoretical predictions. A metalens with a diameter of several tens of microns was designed and fabricated in a thin amorphous silicon film with a thickness of 120 μm and a low aspect ratio, high numerical aperture, and short focal distance equal to a wavelength of 633 nm.

In this paper, spin-orbital conversion in the tight focus of an axial superposition of a high-order (order m) cylindrical vector beam and a beam with linear polarization is theoretically and numerically considered. Although such a beam does not have a spin angular momentum in the initial plane and the third projection of its Stokes vector is equal to zero, subwavelength local regions with a transverse vortex energy flow and with the non-zero third Stokes projection (the longitudinal component of the spin angular momentum) are formed in the focal plane for an odd number m. This means that such a beam with an odd m has regions of elliptical or circular polarization with alternating directions of rotation (clockwise and counterclockwise) in the focus. For an even m, the field is linearly polarized at every point of the focal plane, and the transverse energy flux is absent. These beams can be used to create a micromachine in which two microparticles in the form of gears are captured in the focus of the beam into neighboring local areas in which the energy flow rotates in different directions, and therefore, these gears will also rotate in different directions.

This article deals with issues of assessing the scientific activity of teams of performers when submitting applications to scientific funds. The purpose of the study is to develop new approaches to the use of scientometric indicators to assess the scientific potential of university teams when submitting applications to scientific foundations. Methodological foundations of the research: a systematic approach (considers science as a social institution in an indissoluble connection with society as a whole), a metasystem approach (considers the results of scientific activity as a metasystem, that is, a system with relatively independent components), a probabilistic-statistical approach (considers research activity as a probabilistic process), qualimetric approach (considers the productivity of scientific activity as a latent variable, reflected by a set of criteria). As a result, the authors proposed: an information model of the relationship between the requirements for a scientific project by the customer, and the level of compliance of the scientific potential of the team of performers and a methodology for assessing the scientific potential of the team of performers when applying for the competition. The information model forms the basis of the developed information system for supporting the project activities of ITMO University, which serves to improve the process and increase the efficiency of preparation of draft applications submitted by the university. The proposed methodology is implemented using scientometric indicators, through software algorithms for automated assessment of scientific potential. In the course of an experimental study, the authors have shown that the proposed approaches correlate with the effectiveness of participation in competitions. The proposed solutions have been successfully integrated into the ITMO University, management system.

It is known that angular momentum (AM) is an important characteristic of light, which can be separated into the spin (SAM) and orbital parts (OAM). The dynamical properties of the spin and orbital angular momentums are determined by the polarization and spatial degrees of freedom of light. In addition to optical vortex beams possessing spatial polarization and phase singularities, optical fibers can be used to generate and propagate optical modes with the orbital and spin parts of the angular momentum. In this paper, using the example of hollow-core fibers, we demonstrate the fact that their leaky air core modes also have an orbital part of AM in the case of circular polarization arising from the spin–orbit interaction of the air core modes. The reason for the appearance of AM is the leakage of the air core mode energy.

In this study, we theoretically and experimentally investigate the propagation of a second-order cylindrical vector beam through an aluminum lens which forms a tight focus at the distance of the wavelength. Simulation by the finite-difference time-domain method and the Richards–Wolf formulae produces light field distributions which coincide with experimental measurements provided with scanning near-field optical microscopy. We demonstrate that a pyramidal metallized cantilever with a hole is more sensitive to the transversal component of intensity than to the full intensity or to the Umov–Poynting vector in areas of reverse energy flow.

For detecting the solution quality of different materials we suggested to study their solid components structure with NLCs. The operation process consists of solution drying, thin NLC layer application on solid components and imaging study of deformed NLC structures with polarizing microscopy and software that keep the information on solid components structure. We present new achievements in medicine to illustrate the results of non-invasive detecting of some cancer particularities and erythrocytes pathology. For perfume products we suggest new criterion for detecting scents smell durability. In beverage foods we suggest new technology to examine the difference between original products and counterfeit samples.

Inclusion of the journal Computer Optics in the Emerging Sources Citation Index database is described in this editorial.

The industry of metatuff axes and adzes on the western coast of Onega Lake (Eneolithic period, ca. 3500 – 1500 cal. BC) allows assuming some sort of craft specialization. Excavations of a workshop site Fofanovo XIII, conducted in 2010-2011, provided an extremely large assemblage of artefacts (over 350000 finds from just 30 m2, mostly production debitage). An attempt to estimate the output of production within the excavated area is based on experimental data from a series of replication experiments. Mass-analysis with the aid of image recognition software was used to obtain raw data from flakes from excavations and experiments. Statistical evaluation assures that the experimental results can be used as a basement for calculations. According to the proposed estimation, some 500 – 1000 tools could have been produced here, and this can be qualified as an evidence of “mass-production”.