Resonantly suppressed transmission and anomalously enhanced light absorption in ultrathin metal films

We study light diffraction in the periodically modulated ultrathin metal films both analytically and numerically. Without modulation these films are almost transparent. The periodicity results in the anomalous effects, such as suppression of the transmittance accompanied by a strong enhancement of the absorptivity and specular reflectivity, due to excitation of the surface plasmon polaritons. These phenomena are opposite to the widely known enhanced transparency of periodically modulated optically thick metal films. Our theoretical analysis can be a starting point for the experimental investigation of these intriguing phenomena.Comment: 4 pages, 5 figure

Resistance of two-dimensional superconducting films

We consider the problem of finite resistance R in superconducting films with geometry of a strip of width W near zero temperature. The resistance is generated by vortex configurations of the phase field. In the first type of process, quantum phase slip, the vortex world line in 2+1 dimensional space-time is spacelike (i.e., the superconducting phase winds in time and space). In the second type, vortex tunneling, the world line is timelike (i.e., the phase winds in the two spatial directions) and connects opposite edges of the film. For moderately disordered samples, processes of the second type favor a train of vortices, each of which tunnels only across a fraction of the sample. Optimization with respect to the number of vortices yields a tunneling distance of the order of the coherence length ξ , and the train of vortices becomes equivalent to a quantum phase slip. Based on this theory, we find the resistance ln R ∼ − gW/ξ , where g is the dimensionless normal-state conductance. Incorporation of quantum fluctuations indicates a quantum phase transition to an insulating state for g 1

PERSPECTIVES OF LISOTATHOLOGICAL MONITORING BY MATERIALS OF RESISTANCE OF FUSION SCANNING OF FORESTS BY THE EXAMPLE OF ZHYTOMYR REGIONAL MANAGEMENT OF FOREST AND HORTICULTURAL HOLDING

The actual questions of remote space estimation of forest-pathological state of forests are substantiated, since today it is the least developed section of forest decoding. The preliminary analysis of materials of the space scanning of forests of Zhytomyr region for the purpose of drying out of pathological action of pests and diseases was carried out.The subject of the work is the material of the geoinformation scanning of the forests of the Zhytomyr Oblast Department of Forestry and Hunting for the monitoring of the forest-pathological condition, as well as their comparison with the aerial photographs. This is due to the unstable manifestation and diagnostics on the materials of aerospace shooting of signs of decoding trees and plantations of varying degrees of weakening and drying. The purpose of the work is to study and systematize materials of satellite scanning of forests on the subject of forest-pathological monitoring in the conditions of the Zhytomyr Regional Department of Forestry and Hunting. It has been established that satellite monitoring of forest-pathological condition on the example of Zhytomyr Regional Forestry and Hunting Management Department is the most effective measure for monitoring and forecasting the condition of forests of Zhytomyr region.The basic methods of carrying out works are the calculation and analytical for gathering and processing of the results of geoinformation scanning of forest ecosystems of Zhytomyr Polissya as a result of satellite scanning, as well as monitoring of forest-pathological changes in the forest areas of the Zhytomyr Regional Department of Forestry and Hunting. According to the results of the work, it has been established that satellite scanning of forests of Zhytomyr region gives fairly accurate and true information about the actual condition of forests and their forest-pathological characteristics. This is especially true for arrays affected by the disease with apical bark, six caudal bark, vascular mycosis and are in a semi-dry state. As a result of the conducted research, it was discovered that satellite monitoring of forest-pathological conditions in the Zhytomyr Oblast Department of Forestry and Hunting is the most informative and less costly compared to conducting aerial photographic monitoring with the subsequent decoding of aerial photographs. This will enable detailed forest-pathological forecasting of forest conditions in the conditions of Zhytomyr regional forestry and hunting management.The field of application of research results is the forest enterprises of the Zhytomyr Regional Department of Forestry and Hunting for the forest-pathological forecast of the possibilities of occurrence of various kinds of pathologies in forest soils in order to preserve and protect forest plantations from pests and diseases.The findings of the research are that forest decoding of aerospace surveys is a process of recognition of forest objects depicted on them and the establishment of their quantitative and qualitative characteristics. Forest decryption can be visual (dimensional, analytical), measuring, automatic (computer), as well as complex - analytical-measuring or automated (interactive). In visual decoding, the object under investigation is characterized by signs of decoding its image on an aerial photograph or a space photograph (on a paper carrier or computer screen) with an unarmed eye or with magnifying or stereoscopic devices. In other words, aerospace image information is read and analyzed using the visual and logical devices of the decoder. Its objectivity depends on the experience of the decoders. In the measurement decoding, all or some of the parameters and characteristics of the decoding objects are measured on the pictures by means of mechanical, optical-mechanical, opto-electronic and other measuring instruments, devices, devices and systems. In analytical-measuring decoding combines a visual-logical analysis of the image with the measurement of various parameters of decoding objects. Automatic decryption is based on the recognition of the spectral and morphometric characteristics of the decoding objects, their quantitative and qualitative indicators. In this case, the decryption process is performed with the help of technical means of image processing. The role of the satellite monitoring operator is to create a system, define a specific task and process the captured information through the corresponding programs, as well as support the normal functioning of the satellite system. Automated (interactive) decryption combines the elements of analytical-measuring, executed by the decoder on the image on the computer screen, with automatic decryption. In this case, the information collected is analyzed and processed using technical means of image processing. Depending on the location, the decryption can be field, office (laboratory), aerial or combined. Field decryption is carried out directly on the ground by comparing the image on aerial or space images with nature. The field decoding method is the simplest and most accurate, but it requires a lot of time and effort. Cameral decoding is conducted in laboratory conditions, while the costs of labor of engineering personnel are reduced, there is acceleration of work and a significant reduction in their value. Cameral decryption is always performed with the use of additional mapping, reference and other stock materials. Aerivisional decryption is carried out by comparing the images of the identified objects on aerial or space photographs with the terrain when flying on airplanes or helicopters. The analysis of the informativeness of the satellite and aerial photography of the forest areas of the Zhytomyr Oblast Department of Forestry and Hunting shows that their practical application is possible, as a rule, on the basis of a rational combination of methods of terrestrial and remote non-informative observations.Key words: drying of plantations, forest-pathological monitoring, satellite scanning, survey materials, Zhytomyr Polissya