In recent years, the construction of lateral heterostructures of two-dimensional (2D) monolayers of transition metal dichalcogenides (TMDC) has been attracting considerable interest due to its ...numerous applications in electronic and optoelectronic devices. In this work, the optical absorption coefficient of the Lateral Single Quantum Well (LSQW) based on
MoS
2
/
WSe
2
is analyzed theoretically. For this purpose, we rederive the absorption coefficient equation for LSQW and investigate the parameters affecting the absorption coefficient of LSQW such as the type of polarization and incident angle as well as spin–orbit coupling (SOC). Our results show the significant effect of the spin–orbit effect on the maximum value of the absorption coefficient so that by including the SOC, the values of absorption coefficient increases. We surprisingly found that increasing the well width enhances the optical absorption in LSQW. Our findings and predictions might be implemented in new emerged optovalleytronic devices.
Graphical abstract
(
a
) Absorption coefficient as a function of the photon energy with various incident angle. (
b
) Absorption coefficient as a function of the incident angle.
ABSTRACT
The Deep Extragalactic VIsible Legacy Survey (DEVILS) is an ongoing high-completeness, deep spectroscopic survey of ∼60 000 galaxies to Y < 21.2 mag, over ∼6 deg2 in three well-studied deep ...extragalactic fields: D10 (COSMOS), D02 (XMMLSS), and D03 (ECDFS). Numerous DEVILS projects all require consistent, uniformly derived and state-of-the-art photometric data with which to measure galaxy properties. Existing photometric catalogues in these regions either use varied photometric measurement techniques for different facilities/wavelengths leading to inconsistencies, older imaging data and/or rely on source detection and photometry techniques with known problems. Here, we use the ProFound image analysis package and state-of-the-art imaging data sets (including Subaru-HSC, VST-VOICE, VISTA-VIDEO, and UltraVISTA-DR4) to derive matched-source photometry in 22 bands from the FUV to 500 $\mu$m. This photometry is found to be consistent, or better, in colour analysis to previous approaches using fixed-size apertures (which are specifically tuned to derive colours), but produces superior total source photometry, essential for the derivation of stellar masses, star formation rates, star formation histories, etc. Our photometric catalogue is described in detail and, after internal DEVILS team projects, will be publicly released for use by the broader scientific community.
We investigate the effects of 10.6 μm CO
2
laser irradiation and 572 nm dye laser irradiation on optical properties and laser damage threshold of Nd:glass. We study the transmission, additional ...absorption (AA) spectra, and damage threshold of the samples before and after the irradiation. The results obtained indicate that irradiation of Nd:glass by pulsed CO
2
and dye lasers is extremely effective for decrease of defects and increase in damage thresholds. The damage threshold of Nd:glass increases by a factor of 4.13 for dye laser and a factor of 3.1 for CO
2
laser.
The effect of magnetization of acid before usage (pre-magnetization technique) on the corrosion inhibition of carbon steel (CS) in 7.5, 10 and 12.5 wt % (2.2, 3.0 and 3.8 M) HCl solutions were ...investigated by means of gravimetric weight loss method. Response Surface Methodology (Box-Behnken design) has been used to study and modelling the effects of magnetic field (MF) intensity, acid concentration, and elapsed time on inhibition efficiency. The experiments reveal that pre-magnetization is a suitable inhibitor in HCl solutions. The maximum percentage inhibition efficiency was found to be 93% for 12.5 wt % HCl. The results showed that the inhibition efficiency rises with increasing MF intensity. The surface structure of the CS was examined by SEM (scanning electron microscopy) both in the normal and magnetized HCl solutions.
The experimental study of passively Q-switched, LED-pumped Ce:Nd:YAG laser is reported. The active medium is a 3 mm diameter laser rod with 60 mm length; it is optically pumped with four segments of ...blue LEDs at 460 nm, with each segment consisting of 32 single LEDs. The 14 cm length optical resonator with 2 dielectric mirrors and the reflectivity of 99 and 93 percent at 1064 nm produced more than 200 micro-joules laser spikes at the free-running mode of operation. By using a passive optical switch with 96% initial transmission and 0.6 J electrical pumping energy, the single Q-switch (QS) laser pulse with 240 ns pulse-width and 17 micro-joules optical energy was produced. By increasing the pumping energy to 1.2 J, two nearly similar QS laser pulses were generated. Moreover, we have proposed a method for decreasing the pulse-width and increasing the energy of single QS laser pulse that is based on controlling the pumping rate by shaping the current of LEDs
In this paper, the morphology, roughness and nano structural properties of SiO2/Poly Vinyl Pyrrolidone synthesized with sol gel method, characterized by using scanning electron microscopy, atomic ...force microscopy and GPS132A techniques.The main material taken from oxide silicon with weight percentage of 20, 40, 60, 80 and from poly vinyl pyrrolidone with percentages of 80, 60, 40, 20 is synthesized and are called sample 1, 2, 3 and 4 respectively. The samples usinglower poly vinyl pyrrolidone (PVP:SiO2; 2:3 in Weight) can be suitable choices in producing organic field-effect transistors due to their better structuralquality, less energy loss, less roughness sample surface, higher dielectric constant (K=15.99 ) and better surface morphology as determined with applying DME SPM software and above techniques. This sample can be thus considered as a good element of the future organic field-effect transistors devices.
In this paper, project portfolio selection (PPS) is considered as one of the main steps in project portfolio management (PPM). PPS which depends on different criteria such as strategic, financial, as ...well as project specifications is also suggested for construction contractors. Although it is difficult to consider all these criteria, the decision will be inaccurate when some of them are ignored. The most common multi-criteria decision-making (MCDM) methodologies and geographic information system (GIS) are combined as a method, by which the potential projects obtain a strategic score by the analytical hierarchy process (AHP). Then, they are ranked according to technical criteria by the technique for order preference by similarity to ideal solution (TOPSIS). The proposed approach includes three ordinal phases. First, scoring potential projects due to the company strategy is conducted by the AHP to determine strategic-aligned projects (SAPs). Then, SAPs are ranked by TOPSIS. Finally, the final GIS sheet is prepared by the obtained technical score and communal criteria. This paper provides a clear and comprehensive insight to accept or reject SAPs by form a weighted sheet in GIS. It suggests that CCs select project portfolio according to all the financial and non-financial criteria. This approach can satisfy the PPM principals and resolve some of the shortcomings related to MCDM methods by GIS capacities to reduce complexity so that the decision-makers form project portfolios easily and effectively. This approach is described in a case study.
One of the most important challenges in heavy oil reservoirs is the enhancement of oil recovery. In the last two decades, a new technology, called magnetic water technology, has been used in ...different industries such as concrete. In this technology, by passing water through a magnetic field, some of its physical properties change. In this research, the effects of magnetic water on enhanced oil recovery (EOR) have been studied. A magnetic treatment device was used for the production of magnetic water. Three tests were taken with normal water, weak magnetic water, and strong magnetic water. The results of the experiments showed that the breakthrough event will shorten with an increasing level of magnetism in water. Although the total recovery is approximately the same, it can be concluded that EOR has a reverse relation with the amount of magnetism in water.
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