ENHANCEMENT OF THE ELECTROMAGNETIC FIELD BY PERIODIC STRUCTURES FOR RAMAN SPECTROSCOPY APPLICATION
Journal Title: Вісник Національного університету "Львівська політехніка", серія "Радіоелектроніка та телекомунікації" - Year 2017, Vol 885, Issue 2017
Abstract
Raman spectroscopy is an extremely sensitive and effective method for studying the structure of macromolecules and their changes. The specially designed SERS substrates are one of the ways to enhance Raman signals. Such substrates can significantly increase the sensitivity of optical diagnostics of materials in the ultra-small quantities. It is important for different applications in science, industry and human activity. At present time, the problem of design and optimization of the different substrates for enhance Raman signals remains relevant. The periodic structures on base of, both metal gratings on a dielectric substrate and metal gratings on a metal substrate can be used as SERS-substrates. In this work, modeling of the distribution of an electromagnetic field and an enhanced factor by periodic structures consisting of rectangular diffraction metal (silver) gratings on a dielectric (polycarbonate) and metal (silver) substrates have been carried out for excitation wavelengths of 532 nm (Nd: YAG laser on the second harmonics), 633 nm (He-Ne-laser) and 785 nm (diode laser) for maximum enhancing of Raman signals. The optimal grating parameters are determined which provide maximum concentration of electromagnetic field for these wavelengths of exciting radiation. The modeling results showed that maximum enhanced field is obtained for the given wavelength and grating period only at certain values of the grating thickness and the filling factor. Periodic structures on the basis of the metal grating on the metal substrate showed significantly higher enhance of the electromagnetic field (90 units) compared to structures based on the metal grating on the dielectric substrate142 (15 units). Consequently, such structures are more suitable for effective application as SERSsubstrates.
Authors and Affiliations
H. Petrovska, Iryna Yaremchuk, I. Murvai, Volodymyr Fitio, Yaroslav Bobitski
JOINT DISCOVERY AND ESTIMATION OF INTENSITY OF UNSTATIONARY STREAM OF CALLS
The problem of joint detection and rating intensity of а stream applications in telecommunication system is examined. A mathematical model, which includes a flow model, procedure of estimation of parameters and threshold...
THE ANALYSIS AND MODELING OF QUEUES FORMING AND PROCESSING IN THE NETWORK DEVICES
The investigation has covered buffer resource and queue management as main and the most important network traffic parameter and access control and overload mechanism. Network devices interaction model can performed by th...
NO-REFERENCE ASSESSMENT OF THE GENERALIZED CONTRAST OF COMPLEX MONOCHROME IMAGES
The problem of no-reference measurement of generalized (full integral) contrast of complex (multi-element) monochrome images for objective assessment of their quality is considered in this paper. Different approaches to...
THE EXPANSION OF THE POSSIBILITIES OF THE SYSTEM PROGRAM FUNCTIONS MAOPCs FOR THE STUDY OF LINEAR PERIODICALLY-TIME-VARIABLE CIRCUITS
The system program function MAOPCs is designed to study multivariate analysis and optimization of state linear periodically-time-variable circuits. The architecture of the system MAOPCs is based on the principles of soft...
MATCHING UP OF IMAGES WHICH FORMED BY SENSORS OF DIFFERENT PHYSICAL NATURE IN THE PROCESS OF SIGNAL FUSION IN MULTISPECTRAL MONITORING SYSTEMS
Multispectral monitoring systems are becoming more widely used in which the fusion of information obtained in the form of different spectral images is applied. Direct fusion of such images is impossible in connection wit...