Search results for "Chalcogen"

<title>Photo-induced structural changes in near-surface layers of chalcogenide semiconductors</title>

1997

Photoinduced structural changes in near-surface layers of amorphous As-Se and As-S films have been investigated using the microhardness method. Microhardness via indentation depth data for as-deposited, illuminated and aged in ambient atmosphere films is presented. The results obtained show that photoinduced increase in microhardness of surface layers up to approximately 1 - 1.5 micrometer are more pronounced in comparison with deeper layers. Increase in microhardness of the investigated films under exposure to atmosphere was also observed. Atmosphere-induced effect was more pronounced in the case of As-S films. Photo- and atmosphere-induced effects in the near-surface layers were found to …

Fourth order cascaded Raman shift in As38Se62 chalcogenide suspended core fiber pumped at 1.995 μm

2011

Fourth order cascaded Raman wavelength shift is demonstrated in As 38 Se 62 suspended core fiber using 1995 nm nanosecond source. The measured Raman gain coefficient is∼2×10−11 m/W at 1995 nm. The Raman peaks are reproduced by numerical simulations.

Unveiling the Sulfur–Sulfur Bridge: Accurate Structural and Energetic Characterization of a Homochalcogen Intermolecular Bond

2018

open 12 si MIUR “PRIN 2015” funds (Grant Number 2015F59J3R) By combining rotational spectroscopy in supersonic expansion with the capability of state-of-the-art quantum-chemical computations in accurately determining structural and energetic properties, the genuine nature of a sulfur–sulfur chalcogen bond between dimethyl sulfide and sulfur dioxide has been unveiled in a gas-jet environment free from collision, solvent and matrix perturbations. A SAPT analysis pointed out that electrostatic S⋅⋅⋅S interactions play the dominant role in determining the stability of the complex, largely overcoming dispersion and C−H⋅⋅⋅O hydrogen-bond contributions. Indeed, in agreement with the analysis of the…

ZnS Ultrathin interfacial layers for optimizing carrier management in Sb2S3-based photovoltaics

2021

Antimony chalcogenides represent a family of materials of low toxicity and relative abundance, with a high potential for future sustainable solar energy conversion technology. However, solar cells based on antimony chalcogenides present open-circuit voltage losses that limit their efficiencies. These losses are attributed to several recombination mechanisms, with interfacial recombination being considered as one of the dominant processes. In this work, we exploit atomic layer deposition (ALD) to grow a series of ultrathin ZnS interfacial layers at the TiO2/Sb2S3 interface to mitigate interfacial recombination and to increase the carrier lifetime. ALD allows for very accurate control over th…

Holographic recording in amorphous chalcogenide thin films

2007

Abstract Holographic recording by He–Ne laser (line 632.8 nm) light in amorphous As 0.55 Se 0.45 thin films for different film thickness and grating period was studied. A strong dependence of the diffraction efficiency of the gratings on the readout light wavelength (650 nm, 805 nm and 1150 nm) was observed. A decrease in diffraction efficiency for longer wavelengths is explained by a decrease in the photoinduced changes of refractive index. It is shown that high efficiency gratings can be recorded in As 0.55 Se 0.45 films with a thickness of ∼1 μm.

Optical-field induced volume- and surface-relief formation phenomenon in thin films of vitreous chalcogenide semiconductors

2013

In this report the study of direct recording of the surface relief gratings on amorphous chalcogenide thin (2.5-5μm) films is presented by three different recording setups. Recording was performed on As2S3 by 532nm wavelength laser light. Additionally the evolution of surface relief in dependence from the recording time and polarization has been investigated in detail. The mechanism of the direct recording of surface relief on amorphous chalcogenide films based on the photo-induced plasticity has been discussed.

Metal—Organic Chemical Vapor Deposition Synthesis of Hollow Inorganic-Fullerene-Type MoS2 and MoSe2 Nanoparticles.

2005

Chalcogenide glass hollow core photonic crystal fibers

2010

International audience; We report the first hollow core photonic crystal fibers (HC PCF) in chalcogenide glass. To design the required HC PCF profiles for such high index glass, we use both band diagram analysis to define the required photonic bandgap and numerical simulations of finite size HC PCFs to compute the guiding losses. The material losses have also been taken into account to compute the overall losses of the HC PCF profiles. These fibers were fabricated by the stack and draw technique from Te20As30Se50 (TAS) glass. The fibers we drew in this work are composed of six rings of holes and regular microstructures. Two profiles are presented, one is known as a kagome lattice and the ot…

Mo 3 Q 7 (Q = S, Se) Clusters Containing Dithiolate/Diselenolate Ligands: Synthesis, Structures, and Their Use as Precursors of Magnetic Single‐Compo…

2013

The coordination chemistry of dithiolene and diselenolene ligands towards the all-selenium [Mo3Se7Br6]2– dianion has been investigated. Complexes (nBu4N)2[Zn(dmit)2] (dmit = 1,3-dithia-2-thioxo-4,5-dithiolate) and (nBu4N)2[Zn(dsit)2] (dsit = 1,3-dithia-2-thioxo-4,5-diselenolate) were employed as ligand precursors. The (nBu4N)2[Zn(dmit)2] complex in acetonitrile at reflux showed unexpected reactivity with [Mo3Se7Br6]2– dianion in which the inner Se atoms were replaced by S (all but the μ3-Se atom) to afford a series of mixed chalcogen [Mo3Se7–xSx(dmit)3]2– (x = 0–6) dianions. Reaction of the [Mo3S4Se3Br6]2– dianion with (nBu4N)2[Zn(dmit)2] under similar conditions also produced a mixed dmit-…

chalcogenide materials for nonlinear integreted optics in mid-infrared

2019

Elaboration and characterization of new compositions of chalcogenide materials exhibiting nonlinear effects for integrated optic applications and fabrication of low-loss waveguides.