Surface diffraction on a ψ-circle diffractometer using the χ-axis geometry

2013 ◽  
Vol 46 (3) ◽  
pp. 639-643 ◽  
Author(s):  
Tim T. Fister ◽  
Paul H. Fuoss ◽  
Dillon D. Fong ◽  
Jeffrey A. Eastman ◽  
Chad M. Folkman ◽  
...  
Keyword(s):  
Thin Film ◽  
Incident Angle ◽  
Azimuthal Angle ◽  
Restricted Volume ◽  
Surface Diffraction ◽  
Alternative Configuration ◽  
Diffraction Condition

The restricted volume above and below the sample on a six-circle diffractometer can limit the size and complexity of sample environments used in surface diffraction studies. An alternative configuration of the diffractometer, where the sample normal is aligned parallel to the χ axis, allows for ample space above and below the χ circle for instrumentation. The merits of this approach are outlined and angles are derived for the diffraction condition for constant-incident-angle, constant-sample-azimuthal-angle and specular geometries. Using a version of this code written forSPEC(http://www.certif.com/content/spec/), sample specular and nonspecular crystal truncation rods measured from a 5 nm-thick thin film are presented.

Narrow-frequency sharp-angular filters using all-dielectric cascaded meta-gratings

Nanophotonics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 3443-3450 ◽  
Author(s):  
Wei-Nan Liu ◽  
Rui Chen ◽  
Wei-Yi Shi ◽  
Ke-Bo Zeng ◽  
Fu-Li Zhao ◽  
...  
Keyword(s):  
Thin Film ◽  
Signal To Noise Ratio ◽  
Incident Angle ◽  
Design Strategy ◽  
Transmission Peak ◽  
High Signal ◽  
Waveguide Array ◽  
Signal To Noise ◽  
Center Wavelength ◽  
Noise Ratio

AbstractSelective transmission or filtering always responds to either frequency or incident angle, so as hardly to maximize signal-to-noise ratio in communication, detection and sensing. Here, we propose compact meta-filters of narrow-frequency sharp-angular transmission peak along with broad omnidirectional reflection sidebands, in all-dielectric cascaded subwavelength meta-gratings. The inherent collective resonance of waveguide-array modes and thin film approximation of meta-grating are employed as the design strategy. A unity transmission peak, locating at the incident angle of 44.4° and the center wavelength of 1550 nm, is demonstrated in a silicon meta-filter consisting of two-layer silicon rectangular meta-grating. These findings provide possibilities in cascaded meta-gratings spectroscopic design and alternative utilities for high signal-to-noise ratio applications in focus-free spatial filtering and anti-noise systems in telecommunications.

Monte Carlo calculation of A 3 B (111) ordering transition and surface X-ray intensities

1990 ◽  
Vol 46 (2) ◽  
pp. 86-94 ◽  
Author(s):  
X.-M. Zhu ◽  
H. Zabel
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Calculation ◽  
Incident Angle ◽  
Surface Region ◽  
Conducting Surface ◽  
X Ray ◽  
Main Emphasis ◽  
Simulation Results ◽  
Ordering Transition ◽  
Surface Diffraction

A Monte Carlo simulation of an ordering phase transition in the surface region of a f.c.c.-type A 3 B binary alloy is reported. The main emphasis of this simulation is the evaluation of short and long-range-order correlations near the surface which are used for calculating X-ray intensities under grazing-incident-angle conditions. These calculations suggest effective ways of conducting surface diffraction experiments on order-disorder phase transitions. The simulation results are also compared with available experimental data.

Leveling of thin film surface by low-incident-angle ion milling for HTS SFQ circuits

2005 ◽  
Vol 426-431 ◽  
pp. 1514-1518 ◽  
Author(s):  
K. Nakayama ◽  
Y. Ishimaru ◽  
H. Wakana ◽  
S. Adachi ◽  
T. Hato ◽  
...  
Keyword(s):  
Thin Film ◽  
Incident Angle ◽  
Film Surface ◽  
Ion Milling ◽  
Thin Film Surface

Nondestructive Study of Metal-Silicon Interfaces Using Soft X-Ray Emission Spectroscopy

1993 ◽  
Vol 320 ◽  
Author(s):  
H. Watabe ◽  
M. Iwami ◽  
M. Hirai ◽  
M. Kusaka ◽  
H. Nakamura ◽  
...  
Keyword(s):  
Thin Film ◽  
Valence Band ◽  
Emission Spectroscopy ◽  
Incident Angle ◽  
Bond Formation ◽  
Density Of State ◽  
Angle Variation ◽  
X Ray ◽  
Depth Analysis ◽  
Non Destructive

ABSTRACTSi L2,3 valence band soft x-ray emission spectrum (SXES) due to an e ectron excitation for silicides shows a clear modification from that for Si single crystal. Using this fact in combination with the incident angle variation(IAV) device, a non-destructive in-depth analysis of a Au(thin film)-Si(lll) contact is successfully carried out. Also, the SXES method has clarified the fact that a fair amount of the Si-s valence band density of state (yB-DOS) is included in the upper part of the yB-DOS for a Au-Si alloy, or Au-silicide, due to the Au-Si bond formation, which is a clear contrast to proposals given so far.

Multi-band terahertz metasurface absorber

2017 ◽  
Vol 31 (36) ◽  
pp. 1750354 ◽  
Author(s):  
Xuying Wang ◽  
Qingmin Wang ◽  
Guoyan Dong ◽  
Yanan Hao ◽  
Ming Lei ◽  
...  
Keyword(s):  
Incident Angle ◽  
Ground Plane ◽  
Azimuthal Angle ◽  
Ring Resonators ◽  
Perfect Absorber ◽  
Absorption Mechanism ◽  
Practical Applications ◽  
Dielectric Spacer ◽  
Resonance Frequencies ◽  
Multi Band

A terahertz metasurface perfect absorber with multi-band performance is demonstrated. The absorber is composed of a ground plane and four split-ring resonators (SRRs) with different dimensions, separated by a dielectric spacer. The numerical simulation results illustrate that the proposed absorber has four distinct absorption peaks at resonance frequencies of 4.24, 5.66, 7.22, and 8.97 THz, with absorption rates of 96.8%, 99.3%, 97.3%, and 99.9%, respectively. Moreover, the corresponding full width at half-maximum (FWHM) values are about 0.27, 0.35, 0.32, and 0.42 THz, respectively, which are much broader than those of previously reported absorbers. Besides, the calculated magnetic field distributions allow us to understand the absorption mechanism in detail. The effects of incident angle and azimuthal angle on the absorber are also investigated. The results show that the proposed absorber is partially sensitive to the incident angle, which makes this design promising for practical applications in terahertz imagers and detectors.

Optical Thin Films with Very Low Refractive Index and Their Application in Photonics Devices

2005 ◽  
Vol 901 ◽  
Author(s):  
Jingqun Xi ◽  
Jong Kyu Kim ◽  
Dexian Ye ◽  
Jasbir S. Juneja ◽  
T.-M. Lu ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Refractive Index ◽  
Incident Angle ◽  
Columnar Structure ◽  
Bragg Reflector ◽  
Single Pair ◽  
Scanning Electron Micrographs ◽  
Distributed Bragg Reflector ◽  
Low Refractive Index

AbstractThe refractive index contrast in dielectric multilayer structures, optical resonators and photonic crystals is an important figure of merit, which creates a strong demand for high quality thin films with a very low refractive index. SiO2 nano-rod layers with low refractive indices n = 1.08, the lowest ever reported in thin-film materials, is grown by oblique-angle e-beam deposition of SiO2 with vapor incident angle 85 degree. Scanning electron micrographs reveal a highly porous columnar structure of the low-refractive-index (low-n) film. The gap between the SiO2 nano-rods is ≤50 nm, i.e. much smaller than the wavelength of visible light, and thus sufficiently small to make scattering very small. Optical micrographs of the low-n film deposited on a Si substrate reveal a uniform specular film with no apparent scattering. The unprecedented low index of the SiO2 nano-rod layer is confirmed by both ellipsometry measurements and thin film interference measurements. A single-pair distributed Bragg reflector (DBR) employing the SiO2 nano-rod layer is demonstrated to have enhanced reflectivity, showing the great potential of low-n films for applications in photonic structures and devices.

scholarly journals Deteksi Formalin Menggunakan Surface Plasmon Resonance (SPR) Berbasis Nanopartikel Perak sebagai Pengembangan Awal Teknologi Food Safety

2016 ◽  
Vol 3 (02) ◽  
pp. 201
Author(s):  
Muhammad Khoirul Anam ◽  
Risma Narindra ◽  
Thoyibi T ◽  
Kamsul Abraha
Keyword(s):  
Thin Film ◽  
Surface Plasmon Resonance ◽  
Surface Plasmon ◽  
Plasmon Resonance ◽  
Incident Angle ◽  
Attenuated Total Reflection ◽  
Film System ◽  
Thin Film System ◽  
Nanoparticle System ◽  
Silver Silver

<span>The phenomena of surface plasmon resonance (SPR) has been observed. SPR is reflectance <span>curve as a function of incident angle in Kretschmann configuration. Surface plasmon is elec<span>tromagnetic waves propagation in the interface area between metal and dielectric that can be <span>excited by using attenuated total reflection (ATR) method. The result of experiment explains <span>that the SPR angle on the thin film system of the prism/silver 1 and the prism/silver 2 is (42.8<br /><span>± 0,05)º with the reflectance value 0.32 and 0.44 respectively. On the prism/silver/silver <span>nanoparticle system, it is obtained that SPR angle value is (4,29 ± 0,05) with the reflectance <span>value 0.29 for the silver 1 and 0.31 for the silver 2. After the thin film system is added with <span>40% of formalin, SPR angle becomes (43,0 ± 0,05)º with the reflectance value 0.44. Then, af<span>ter the thin film system is added with 100% of formalin, SPR angle becomes (43,2 ± 0,05)º<br /><span>with the reflectance value 0.4. The shifting SPR angle shows that SPR have capability as <span>formalin sensor.</span></span></span></span></span></span></span></span></span></span></span><br /></span>

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