Amorphous Diamond Films Deposited by Pulsed-Laser Ablation: the Optimum Carbon-Ion Kinetic Energy and Effects of Laser Wavelength

1998 ◽  
Vol 526 ◽  
Author(s):  
Douglas H. Lowndes ◽  
Vladimir I. Merkulov ◽  
A. A. Puretzky ◽  
D. B. Geohegan ◽  
G. E. Jellison ◽  
...  
Keyword(s):  
Optical Properties ◽  
Laser Ablation ◽  
Kinetic Energy ◽  
Energy Gap ◽  
Spot Size ◽  
Laser Wavelength ◽  
Film Deposition ◽  
Carbon Ions ◽  
Carbon Ion ◽  
Beam Focusing

AbstractA systematic study has been made of changes in the bonding and optical properties of hydrogen-free tetrahedral amorphous carbon (ta-C) films, as a function of the kinetic energy of the incident carbon ions measured under film-deposition conditions. Ion probe measurements of the carbon ion kinetic energies produced by ArF and KrF laser ablation of graphite are compared under identical beam-focusing conditions. Much higher C+ kinetic energies are produced by ArF-laser ablation than by KrF for any given fluence and spot size. Electron energy loss spectroscopy and scanning ellipsometry measurements of the sp3 bonding fraction, plasmon energy, and optical properties reveal a well-defined optimum kinetic energy of 90 eV to deposit ta-C films having the largest sp3 fraction and the widest optical (Tauc) energy gap (equivalent to minimum near-gap optical absorption). Tapping-mode atomic force microscope measurements show that films deposited at near-optimum kinetic energy are extremely smooth, with rms roughness of only ~ 1 Å over distances of several hundred nm, and are relatively free of particulates.

Structure and optical properties of amorphous diamond films prepared by ArF laser ablation as a function of carbon ion kinetic energy

1998 ◽  
Vol 73 (18) ◽  
pp. 2591-2593 ◽  
Author(s):  
Vladimir I. Merkulov ◽  
Douglas H. Lowndes ◽  
G. E. Jellison ◽  
A. A. Puretzky ◽  
D. B. Geohegan
Keyword(s):  
Optical Properties ◽  
Laser Ablation ◽  
Kinetic Energy ◽  
Diamond Films ◽  
Carbon Ion ◽  
Ion Kinetic Energy ◽  
Arf Laser

scholarly journals EFFECT OF THICKNESS ON THE STRUCTURE AND OPTICAL PROPERTIES OF LASER-INDUCED PLASMA CDO THIN FILMS

2021 ◽  
Vol 03 (03) ◽  
pp. 41-50
Author(s):  
Hiyam Ch. MAJED
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Energy Gap ◽  
Plasma Deposition ◽  
Cadmium Oxide ◽  
Laser Wavelength ◽  
Dielectric Constants ◽  
Laser Induced Plasma ◽  
Glass Substrates ◽  
Cdo Thin Films

Thin films of cadmium oxide (CdO) deposited on glass substrates using Nd-YAG laser wavelength (alpha= 532 nm) and period time (10ns) via laser-induced plasma deposition technique (PLD). The structural properties of these films have been described as a change in thickness (200 , 400 ,and 1000) nm) at substrate temperature of (400 ° C) and energy flounce of (0.4 J / cm2). The X-ray diffraction results show that he mean size of crystallite measured using Scherer formula to adjust the thickness of 200 nm, 400 nm and 1000 nm of CdO thin films is 47 nm, 64 nm and 78 nm respectively .Also the optical properties which included transmittance, absorbance , energy gap and optical constant such as the Refractive index, extinction coefficient real and imaginary parts of dielectric constants were determined .

UV Tunable Laser Ablation of YBa2Cu3Ox+6: Changes in the Product Population and Kinetic Energy Distributions as a Function of the Laser Wavelength and Target Bulk Temperature

1990 ◽  
Vol 191 ◽  
Author(s):  
L. Wiedeman ◽  
H. Helvajian
Keyword(s):  
Laser Ablation ◽  
Kinetic Energy ◽  
Optical Transition ◽  
Tunable Laser ◽  
Product Formation ◽  
Laser Wavelength ◽  
Bulk Temperature ◽  
Uv Laser ◽  
Laser Fluences ◽  
Population Distributions

ABSTRACTWe have conducted two separate experiments in the UV laser ablation of a sintered Yba2Cu3Ox+6wafer. We have measured the photoejected population distributions using selected UV laser wavelengths (4.01, 4.17 and 4.35 eV) near the 4.1 eV optical transition in Yba2Cu3Ox+6 In addition, we have measured the change in the ejected species kinetic energy as a function of the target bulk temperature. All the experiments were conducted at laser fluences well below the plasma formation threshold, and near that for product formation. Our results show that the UV laser ablation, at threshold fluences, proceeds via a nonthermal electronic excitation mechanism.

scholarly journals Preparation of Nanostructured HgI2 Nanotubes /Si Photodetector by Laser Ablation in Liquid

2021 ◽  
Author(s):  
Amnah S. Abd-Alrahman ◽  
Raid Ismail ◽  
Mudhafar A. Mohammed
Keyword(s):  
Optical Properties ◽  
Electron Microscope ◽  
Laser Ablation ◽  
Energy Gap ◽  
Average Length ◽  
Average Particle Size ◽  
Average Diameter ◽  
Average Particle ◽  
Optical Energy Gap ◽  
Laser Ablation In Liquid

Abstract In this work, HgI2 nanotubes/Si heterojunction has been prepared by pulsed laser ablation in ethanol at laser fluence of 12.7 J/cm2. The structural and optical properties of HgI2 nanotubes (NTs) are studied. The X-ray diffraction (XRD) result shows the presence of the mixture of tetragonal and orthorhombic phases of HgI2. The optical properties results show that the optical energy gap of HgI2 NTs was 2.98 eV measured at room temperature. The photoluminescence (PL) spectra of HgI2 display a single emission centered at 535nm. Fourier transformed infrared (FT-IR) results reveal the existence of small bonds at 612 and 1102 cm− 1. Scanning electron microscope (SEM) image show formation of nanotubes and spherical nanoparticles with average particle size of 23nm. Transmission electron microscope (TEM) image of HgI2 confirms the formation of nanotubes morphology with an average diameter of 80nm and an average length of 1.6µm. The I-V curve of HgI2 NTs/p-Si heterojunction were measured at dark and illumination. The responsivity of HgI2 NTs/p-Si heterojunction photodetector is 1.09A/W at 450 and the detectivity and external quantum efficiency are 3.6 ×1012 Jones at 450 and 3×102% at 400nm, respectively, without using post annealing.

scholarly journals CdSe/ZnS Core/Shell for Luminescent Solar Concentrator

2020 ◽  
pp. 1645-1649
Author(s):  
Eman Abd alkareem Fadhil ◽  
Manal Madhat Abdullah
Keyword(s):  
Optical Properties ◽  
Solar Cell ◽  
Silicon Solar Cell ◽  
Energy Gap ◽  
Spectral Response ◽  
Film Deposition ◽  
Core Shell ◽  
Halogen Lamp ◽  
Efficiency Gain ◽  
Over The Top

Fabrication and investigation of the properties of CdSe/ZnS core/shell for the luminescent solar concentrates (LSC) application is presented. An increase of the efficiency of a silicon solar cell was obtained by applying the LSC. The increase was a result of the optical properties of the semiconductor nanoparticles CdSe/ZnS core/shell that were deposited over the top surface of the silicon solar cell facing the illumination source (Halogen lamp). The gravity force was invested for the film deposition process.The optical properties of these nanoparticles were studied. The absorption spectra for the CdSe/ZnS core-shell were 270-600nm, i.e., located within the spectral response area of the examined solar cell. The energy gap values for CdSe were 2.5 eV and 3.3eV for ZnS. X-Ray Diffraction (XRD) analysis was adopted and showed that the particle dimensions are within the nanometer scale.The efficiency value of the bare solar cell was 7.3%, whereas the value was increased to 8.0 % by applying the CdSe/ZnS core/shell LSC, indicating an efficiency gain percentage of 9.59%.

Observations on the growth of YBa2Cu3O7-δ thin films on MgO by pulsed-laser ablation

1991 ◽  
Vol 49 ◽  
pp. 1068-1069
Author(s):  
M. Grant Norton ◽  
C. Barry Carter
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Laser Ablation ◽  
Substrate Surface ◽  
Pulsed Laser ◽  
Pulsed Laser Ablation ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Laser Ablation Process ◽  
Deposition Parameters

Pulsed-laser ablation has been widely used to produce high-quality thin films of YBa2Cu3O7-δ on a range of substrate materials. The nonequilibrium nature of the process allows congruent deposition of oxides with complex stoichiometrics. In the high power density regime produced by the UV excimer lasers the ablated species includes a mixture of neutral atoms, molecules and ions. All these species play an important role in thin-film deposition. However, changes in the deposition parameters have been shown to affect the microstructure of thin YBa2Cu3O7-δ films. The formation of metastable configurations is possible because at the low substrate temperatures used, only shortrange rearrangement on the substrate surface can occur. The parameters associated directly with the laser ablation process, those determining the nature of the process, e g. thermal or nonthermal volatilization, have been classified as ‘primary parameters'. Other parameters may also affect the microstructure of the thin film. In this paper, the effects of these ‘secondary parameters' on the microstructure of YBa2Cu3O7-δ films will be discussed. Examples of 'secondary parameters' include the substrate temperature and the oxygen partial pressure during deposition.

Self-Assembly Optical Components

2003 ◽  
Vol 771 ◽  
Author(s):  
Pavel I. Lazarev ◽  
Michael V. Paukshto ◽  
Elena N. Sidorenko
Keyword(s):  
Optical Properties ◽  
Self Assembly ◽  
Crystalline State ◽  
Liquid Crystalline ◽  
Film Deposition ◽  
X Ray Diffraction ◽  
Optical Components ◽  
Crystal Film ◽  
Solid Film ◽  
Thin Crystal

AbstractWe report a new method of Thin Crystal Film deposition. In the present paper we describe the method of crystallization, structure, and optical properties of Bisbenzimidazo[2,1-a:1',2',b']anthra[2,1,9-def:6,5,10-d'e'f']-diisoquinoline-6,9-dion (mixture with cis-isomer) (abbreviated DBI PTCA) sulfonation product. The Thin Crystal Film has a thickness of 200-1000 nm, with anisotropic optical properties such as refraction and absorption indices. X-ray diffraction data evidences a lyotropic liquid crystalline state in liquid phase and crystalline state in solid film. Anisotropic optical properties of the film make it useful in optical devices, e.g. liquid crystal displays.

scholarly journals Ridge waveguide lasers in Nd:GGG crystals produced by swift carbon ion irradiation and femtosecond laser ablation

2012 ◽  
Vol 20 (9) ◽  
pp. 9763 ◽  
Author(s):  
Yuechen Jia ◽  
Ningning Dong ◽  
Feng Chen ◽  
Javier R. Vázquez de Aldana ◽  
Sh. Akhmadaliev ◽  
...  
Keyword(s):  
Laser Ablation ◽  
Femtosecond Laser ◽  
Ion Irradiation ◽  
Femtosecond Laser Ablation ◽  
Ridge Waveguide ◽  
Carbon Ion ◽  
Waveguide Lasers ◽  
Ridge Waveguide Lasers
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