INVESTIGATION OF THERMAL RADIATION ANGULAR AND POLARIZATION CHARACTERISTICS OF ONE-DIMENSIONAL PHOTONIC STRUCTURES ON A FINITE SUBSTRATE

2021 ◽  
Vol 56 ◽  
pp. 83-88
Author(s):  
V. P. Maslov ◽  
Keyword(s):  
Thermal Radiation ◽  
Experimental Studies ◽  
Radiation Energy ◽  
Infrared Range ◽  
Photonic Structure ◽  
Ir Radiation ◽  
Directional Diagram ◽  
One Dimensional ◽  
Photonic Structures ◽  
Polarization Characteristics

One-dimensional photonic structures (PS) are the layered metamaterials, which optical properties are due to interference effects within the structure. Due to the interaction of electromagnetic waves with the periodic structure, the thermal radiation (TR) of such PS has the features of coherent: it has a selective spectrum and a petal pattern. The relevance of TR PS research is due to the search for new materials to create sources of infrared (IR) radiation in the middle and far IR range (with a wavelength > 5 μm). The second important area of application of the radiating properties of the PS is the creation of non-radiating coatings to remove unwanted TR from the heated surfaces of the IR devices. Despite the fact that the irradiative properties of PS have been studied quite well, in the literature insufficient attention is paid to the influence of the finite substrate on the parameters of TR structures. The influence of a finite incoherent substrate on the angular and polarization characteristics of the thermal radiation of the system (photonic structure)/substrate has been investigated. Systems consisting of plane-parallel Ge or Si plates as PS and incoherent BaF2, BaF2/Al and Al substrates were used in experimental studies. It has been established, the contrast and amplitude of the directional diagram petals of the TR system depend on the ratio of the optical characteristics of the photonic structure and the substrate. The presence of a strongly reflective substrate eliminates the difference between the angular dependences of the s- and p-polarized components of the TR. In the case when the PS is placed on a transparent incoherent substrate with a lower refractive index, there is an increase in the p-polarized component of the TR and the suppression of the s-polarized. The thermal imaging picture of the TR angular distribution of the Si/Al system has been recorded and it was experimentally proved that the TR of photonic systems exhibits circular patterns. The results of the work can be used in the development of narrowband emitters in the middle and far infrared range, coatings to increase radiation energy exchange and coatings with minimal emissivity that are invisible in the thermal range.

scholarly journals Features of thermal radiation of one-dimensional photonic structures on an absorbing substrate

2021 ◽  
Vol 24 (04) ◽  
pp. 444-449
Author(s):  
V.P. Maslov ◽  
◽  
V.O. Morozhenko ◽  
N.V. Kachur ◽  
◽  
...  
Keyword(s):  
Thermal Radiation ◽  
Narrow Band ◽  
Experimental Studies ◽  
Theoretical Research ◽  
Optical Parameters ◽  
Photonic Structure ◽  
One Dimensional ◽  
Wide Range ◽  
System Components ◽  
Absorbing Substrate

The dependences of the thermal radiation (TR) lines contrast and amplitude of the systems (photonic structure)/substrate on the optical characteristics of both the photonic structure and the substrate have been investigated theoretically and experimentally. As it has been ascertained, these dependences demonstrate non-monotonic behavior, and the characteristics of the system TR can both increase and decrease depending on the ratio of individual optical parameters of the system components. The results of theoretical research were confirmed by experimental studies of TR systems Ge/GaAs, Ge/GaAs/Al, GaAs/Au and GaAs/(opaque substrate). The results of the research can be used in the development of narrow-band emitters for the middle and far IR range, which can be applied in the optical infrared devices for a wide range of applications.

scholarly journals Realization of Twenty Monochromatic Beams using Photonic Structure via Principle of Filtering

2021 ◽  
Author(s):  
K.P. Swain ◽  
Subhankar Das ◽  
Soumya Ranjan Samal ◽  
Sanjay Kumar Sahu ◽  
Gopinath Palai
Keyword(s):  
Wave Equations ◽  
Silicon Monoxide ◽  
Expansion Method ◽  
Critical Parameters ◽  
Infrared Range ◽  
Photonic Structure ◽  
Plane Wave Expansion Method ◽  
One Dimensional ◽  
Different Types ◽  
Silicon Based

Abstract The current work employs silicon-based one dimensional photonic structure which delivers ‘20’ different types of monochromatic beams (wavelengths) via filtering action. The I/P signals are essentially varies from visible to short infrared range to justify the work. Though similar type of works related to filtering application are found in the literature, the present research deals with an output signal which could be deployed in different purposes vis-à-vis dentistry, dermatology, spectroscopy, printing, holography, barcode scanning etc. The physicality of this work incorporates 68 layers of silicon monoxide and silicon based one-dimensional optical waveguide along with their configuration where the plane wave expansion method does fulfill the nitty-gritty of required mathematics to solve out electromagnetic wave equations. Reflectance and transmittance characteristics along with the absorbance are the critical parameters that substantiate the said application.

A Study of Creating One-Dimensional Objects with Pulse Selective Laser Melting

2020 ◽  
pp. 26-35
Author(s):  
M.A. Melnikova ◽  
M.V. Taskants ◽  
A.A. Kholopov ◽  
A.A. Tareva ◽  
A.A. Volkova
Keyword(s):  
Selective Laser Melting ◽  
Experimental Studies ◽  
Radiation Energy ◽  
Laser Source ◽  
Laser Melting ◽  
Continuous Laser ◽  
Optimal Range ◽  
One Dimensional ◽  
Aircraft Manufacturing ◽  
316L Steel

The widespread use and implementation of selective laser melting (SLM) technology entails active development in this area, especially for parts with complex internal circuits used in aircraft manufacturing. In this technology, a continuous laser source is usually used as a radiation source. Along with all the advantages, this technology has a number of detrimental features and disadvantages that can be avoided by using a pulsed laser. In this study, the AISI 316L steel was selected as the powder. The possibility of creating tracks by pulsed selective laser melting was examined with a focus on determining the parameters that had the highest impact on the process of object formation. The analysis of the experimental studies carried out by this method showed that the main parameters affecting the track size were the pulse duration and instantaneous radiation energy. The calculated mathematical model made it possible to establish the basic dependences and present the optimal range of parameters to achieve the predicted processing result.

scholarly journals Ag2S QDs/Si Heterostructure-Based Ultrasensitive SWIR Range Detector

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 861 ◽  
Author(s):  
Ivan Tretyakov ◽  
Sergey Svyatodukh ◽  
Aleksey Perepelitsa ◽  
Sergey Ryabchun ◽  
Natalya Kaurova ◽  
...  
Keyword(s):  
Room Temperature ◽  
Low Cost ◽  
Photovoltaic Effect ◽  
Experimental Studies ◽  
Surface States ◽  
Short Wave ◽  
Oxide Semiconductor ◽  
Infrared Range ◽  
Ir Radiation ◽  
Semiconducting Properties

In the 20th century, microelectronics was revolutionized by silicon—its semiconducting properties finally made it possible to reduce the size of electronic components to a few nanometers. The ability to control the semiconducting properties of Si on the nanometer scale promises a breakthrough in the development of Si-based technologies. In this paper, we present the results of our experimental studies of the photovoltaic effect in Ag2S QD/Si heterostructures in the short-wave infrared range. At room temperature, the Ag2S/Si heterostructures offer a noise-equivalent power of 1.1 × 10−10 W/√Hz. The spectral analysis of the photoresponse of the Ag2S/Si heterostructures has made it possible to identify two main mechanisms behind it: the absorption of IR radiation by defects in the crystalline structure of the Ag2S QDs or by quantum QD-induced surface states in Si. This study has demonstrated an effective and low-cost way to create a sensitive room temperature SWIR photodetector which would be compatible with the Si complementary metal oxide semiconductor technology.

One-Dimensional Contact Pressure Distribution of Radial Tires in Motion

1995 ◽  
Vol 23 (2) ◽  
pp. 116-135 ◽  
Author(s):  
H. Shiobara ◽  
T. Akasaka ◽  
S. Kagami ◽  
S. Tsutsumi
Keyword(s):  
Pressure Distribution ◽  
Contact Pressure ◽  
Experimental Studies ◽  
Rolling Resistance ◽  
Leading Edge ◽  
Forward Direction ◽  
Contact Pressure Distribution ◽  
Support Ring ◽  
One Dimensional ◽  
Lowered Pressure

Abstract The contact pressure distribution and the rolling resistance of a running radial tire under load are fundamental properties of the tire construction, important to the steering performance of automobiles, as is well known. Many theoretical and experimental studies have been previously published on these tire properties. However, the relationships between tire performances in service and tire structural properties have not been clarified sufficiently due to analytical and experimental difficulties. In this paper, establishing a spring support ring model made of a composite belt ring and a Voigt type viscoelastic spring system of the sidewall and the tread rubber, we analyze the one-dimensional contact pressure distribution of a running tire at speeds of up to 60 km/h. The predicted distribution of the contact pressure under appropriate values of damping coefficients of rubber is shown to be in good agreement with experimental results. It is confirmed by this study that increasing velocity causes the pressure to rise at the leading edge of the contact patch, accompanied by the lowered pressure at the trailing edge, and further a slight movement of the contact area in the forward direction.

STUDY OF EXTERNAL MASS TRANSFER DURING DRYING OF BERRY RAW MATERIALS TAKING INTO THE SHRINKAGE PHENOMENON

2019 ◽  
Author(s):  
А.В. АКУЛИЧ ◽  
Л.А. ГОСТИНЩИКОВА
Keyword(s):  
Mass Transfer ◽  
Energy Supply ◽  
Raw Materials ◽  
Mass Transfer Rate ◽  
Experimental Studies ◽  
Volume Shrinkage ◽  
External Mass Transfer ◽  
Transfer Coefficients ◽  
Ir Radiation ◽  
Criterial Equations

Исследованы закономерности внешнего массообмена при сушке ягодного сырья для различных способов энергоподвода. Установлено, что ягоды при сушке подвержены значительной объемной (72–81%) и линейной (35–43%) усадке, которую необходимо учитывать при расчете коэффициентов массоотдачи. Объекты исследования – ягоды черники, красной и черной смородины. Проведены экспериментальные исследования по сушке ягодного сырья при конвективном и конвективном с ИК-излучением способах энергоподвода. Исследования проведены при скорости сушильного агента хса1,2 м/с и температуре tса 70°С. Получены критериальные уравнения внешнего массоообмена при сушке ягод для периода постоянной скорости, учитывающие объемную усадку. Определено, что при сушке с конвективным энергоподводом объемная усадка при одном и том же значении критерия Рейнольдса оказывает на 12–20% большее влияние на интенсивность массоообмена для красной смородины по сравнению с черникой и черной смородиной. При сушке с конвективным энергоподводом, ИК-излучением и предварительным прокалыванием объемная усадка наиболее существенно влияет на массообмен для черной смородины, протекающий в 1,5–1,8 раза интенсивнее по сравнению с черникой и красной смородиной. Полученные критериальные уравнения могут быть использованы при расчете и проектировании установок для сушки ягодного сырья. The laws of external mass transfer during drying of berry raw materials for various methods of energy supply are investigated. It is established that the berries during drying are subject to significant volumetric (72–81%) and surface (35–43%) shrinkage, which must be taken into account when calculating the mass transfer coefficients. The objects of the study were various berries: blueberries, red and black currants. Experimental studies have been carried out on the drying of selected berries both in the case of convective and convective methods with IR radiation. Investigations were carried out at a drying agent velocity хса1,2 m/s and its temperature tca70°С. The criterion equations of external mass transfer during drying of berries for a period of constant speed, taking into account the volume shrinkage, are obtained. It was determined that during drying with convective energy supply, volume shrinkage with the same value of the Reynolds criterion on 12–20% has a greater effect on the mass transfer rate for red currants. When drying with convective energy supply, IR radiation and preliminary piercing, the volume shrinkage most significantly affects the mass transfer for black currants, which is 1,5–1,8 times more intense than blueberries and red currants. The obtained criterial equations can be used in the calculation and design of berries dryers.

One-dimensional long-range plasmonic-photonic structures

2010 ◽  
Vol 35 (4) ◽  
pp. 550 ◽  
Author(s):  
W. Mu ◽  
D. B. Buchholz ◽  
M. Sukharev ◽  
J. I. Jang ◽  
R. P. Chang ◽  
...  
Keyword(s):  
Long Range ◽  
One Dimensional ◽  
Photonic Structures
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