The exact solutions for the viscous fluid through a porous slit with linear ab- sorption are obtained. The Stokes equation with non-homogeneous boundary conditions is solved to get the expressions for the velocity com...The exact solutions for the viscous fluid through a porous slit with linear ab- sorption are obtained. The Stokes equation with non-homogeneous boundary conditions is solved to get the expressions for the velocity components, pressure distribution, wall shear stress, fractional absorption, and leakage flux. The volume flow rate and mean flow rate are found to be useful in obtaining a convenient form of the longitudinal velocity component and pressure difference. The points of the maximum velocity components for a fixed axial distance are identified. The value of the linear absorption parameter is ran- domly chosen, and the rest available data of the rat kidney to the tabulate pressure drop and fractional absorption are incorporated. The effects of the linear absorption, uniform absorption, and flow rate parameters on the flow properties are discussed by graphs. It is found that forward flow occurs only if the volume flux per unit width is greater than the absorption velocity throughout the length of the slit, otherwise back flow may occur. The leakage flux increases with the increase in the linear absorption parameter. Streamlines are drawn to help the analysis of the flow behaviors during the absorption of the fluid flow through the renal tubule and purification of blood through an artificial kidney.展开更多
This paper presents an investigation on the self-focusing/defocusing of chirped Gaussian laser beam in collisional plasma with linear absorption. We have derived the differential equation for the beam width parameter ...This paper presents an investigation on the self-focusing/defocusing of chirped Gaussian laser beam in collisional plasma with linear absorption. We have derived the differential equation for the beam width parameter by using WKB and paraxial approximations and solved it numerically. The effect of chirp and other laser plasma parameters is seen on the behavior of beam width parameter with dimensionless distance of propagation. The results are discussed and presented graphically. Our simulation results show that the amplitude of oscillations decreases with the distance of propagation. Due to collisional frequency, the laser beam shows fast divergence which can be minimized by the introduction of chirp parameter. The chirp decreases the effect of defocusing and increases the ability of self-focusing of laser beam in collisional plasma.展开更多
In photolithography,shortening the exposure wavelength from ultraviolet to extreme ultraviolet(EUV,13.5 nm)and soft X-ray region in terms of beyond EUV(BEUV,6.X nm)and water window X-ray(WWX,2.2–4.4 nm)is expected to...In photolithography,shortening the exposure wavelength from ultraviolet to extreme ultraviolet(EUV,13.5 nm)and soft X-ray region in terms of beyond EUV(BEUV,6.X nm)and water window X-ray(WWX,2.2–4.4 nm)is expected to further miniaturize the technology node down to sub-5 nm level.However,the absorption ability of molecules in these ranges,especially WWX region,is unknown,which should be very important for the utilization of energy.Herein,the molar absorption cross sections of different elements at 2.4 nm of WWX were firstly calculated and compared with the wavelengths of 13.5 nm and 6.7 nm.Based on the absorption cross sections in these ranges and density estimation results from the density-functional theory calculation,the linear absorption coefficients of typical resist materials,including metal-oxy clusters,organic small molecules,polymers,and photoacid generators(PAGs),are evaluated.The analysis suggests that the Zn cluster has higher absorption in BEUV,whereas the Sn cluster has higher absorption in WWX.Doping PAGs with high EUV absorption atoms improves chemically amplified photoresist(CAR)polymer absorption performance.However,for WWX,it is necessary to introduce an absorption layer containing high WWX absorption elements such as Zr,Sn,and Hf to increase the WWX absorption.展开更多
Based on the Schr ¨odinger equation for envelope function in the effective mass approximation, linear and nonlinear optical absorption coefficients in a multi-subband lens quantum dot are investigated. The effect...Based on the Schr ¨odinger equation for envelope function in the effective mass approximation, linear and nonlinear optical absorption coefficients in a multi-subband lens quantum dot are investigated. The effects of quantum dot size on the interband and intraband transitions energy are also analyzed. The finite element method is used to calculate the eigenvalues and eigenfunctions. Strain and In-mole-fraction effects are also studied, and the results reveal that with the decrease of the In-mole fraction, the amplitudes of linear and nonlinear absorption coefficients increase. The present computed results show that the absorption coefficients of transitions between the first excited states are stronger than those of the ground states. In addition, it has been found that the quantum dot size affects the amplitudes and peak positions of linear and nonlinear absorption coefficients while the incident optical intensity strongly affects the nonlinear absorption coefficients.展开更多
In the framework of effective mass approximation, we theoretically investigate the electronic structure of the Si δ-doped InAIN/GaN single quantum well by solving numerically the coupled equations Schrodinger-Poisson...In the framework of effective mass approximation, we theoretically investigate the electronic structure of the Si δ-doped InAIN/GaN single quantum well by solving numerically the coupled equations Schrodinger-Poisson self-consistently. The linear, nonlinear optical absorption coefficients and relative refractive index changes are calculated as functions of the doping concentration and its thickness. The obtained results show that the position and the amplitude of the linear and total optical absorption coefficients and the refractive index changes can be modified by varying the doping concentration and its thickness. In addition, it is found that the maximum of the optical absorption can be red-shifted or blue-shifted by varying the doping concentration. The obtained results are important for the design of various electronic components such as high-power FETs and infrared photonic devices.展开更多
In this paper, a new model is proposed for manipulating the Kerr nonlinearity of right-hand circular probe light in a monolayer of graphene nanostructure. By using the density matrix equations and quantum optical appr...In this paper, a new model is proposed for manipulating the Kerr nonlinearity of right-hand circular probe light in a monolayer of graphene nanostructure. By using the density matrix equations and quantum optical approach, the third-order susceptibility of probe light is explored numerically. It is realized that the enhanced Kerr nonlinearity with zero linear absorption can be provided by selecting the appropriate quantities of controllable parameters, such as Rabi frequency and elliptical parameter of elliptical polarized coupling field. Our results may be useful applications in future all-optical system devices in nanostructures.展开更多
Graphene oxide(GO)is a two-dimensional carbon material with a graphene-like structure and many oxygen-containing functional groups,and in recent years from research into the unique optical properties of GO,GO-based co...Graphene oxide(GO)is a two-dimensional carbon material with a graphene-like structure and many oxygen-containing functional groups,and in recent years from research into the unique optical properties of GO,GO-based composite materials formed by combining with other materials have shown improved overall performance.Reported here is an investigation of how doping with Ni,Fe,and Ag nanoparticles affects the linear and nonlinear optical properties of GO films.The morphology and structure of films of GO,GO with Ni nanoparticles,GO with Fe nanoparticles,and GO with Ag nanoparticles were studied by laser scanning confocal microscopy,SEM,energy dispersive spectroscopy,XRD,and Raman spectroscopy.UV-visible absorption spectra were used to study the optical absorption properties,and the optical band gaps of GO and the composites were calculated from those spectra via Tauc plots.The results show that the band gaps of GO films can be effectively regulated by metal nanoparticles,and so the properties of GO composites can be manipulated.The nonlinear optical properties of GO and GO-metal-nanoparticle composite films were studied by femtosecond laser Z-scanning.The results show that the femtosecond laser power can be tuned to the optical limiting behavior of GO.The strong synergistic coupling effect between metal nanoparticles and GO enhances the nonlinear absorption and nonlinear refraction of composite thin films.The nonlinear absorption coefficient of the composite thin films is improved significantly,and the optical limiting properties are excellent.GO-metal-nanoparticle composite materials have potential applications and advantages in improving optical absorption,band-gap control,and optical limiting.They can promote the expansion of GO composite materials in various practical applications and are candidates for good optical materials,opening the way to GO photonics.展开更多
For several types of the applied electric field configuration on the normal-zigzag black phosphorus nanoribbon(nZZ-BPNR)we investigate the band structure and the linear optical absorption spectrum,especially for the e...For several types of the applied electric field configuration on the normal-zigzag black phosphorus nanoribbon(nZZ-BPNR)we investigate the band structure and the linear optical absorption spectrum,especially for the edge states and the corresponding low-energy absorption peaks.The obtained results show that the applied electric field can not only open another band gap at k=0.5 point,but also can change completely the spacial probabilities of edge states in the two edge bands.The strength of electric field can tune the two band gaps at the Γ point and 0.5 point.Further,one remarkable feature is that the forbidden transitionallowed.The lowest-excited-energy linear absorption peakfrom the transition between two edge bands at the Γ point.Finally,in comparison with the lowest-excited-energy peaks among various configurations,the second type of electric field configuration can move this peak blue-shift larger than other configurations.展开更多
文摘The exact solutions for the viscous fluid through a porous slit with linear ab- sorption are obtained. The Stokes equation with non-homogeneous boundary conditions is solved to get the expressions for the velocity components, pressure distribution, wall shear stress, fractional absorption, and leakage flux. The volume flow rate and mean flow rate are found to be useful in obtaining a convenient form of the longitudinal velocity component and pressure difference. The points of the maximum velocity components for a fixed axial distance are identified. The value of the linear absorption parameter is ran- domly chosen, and the rest available data of the rat kidney to the tabulate pressure drop and fractional absorption are incorporated. The effects of the linear absorption, uniform absorption, and flow rate parameters on the flow properties are discussed by graphs. It is found that forward flow occurs only if the volume flux per unit width is greater than the absorption velocity throughout the length of the slit, otherwise back flow may occur. The leakage flux increases with the increase in the linear absorption parameter. Streamlines are drawn to help the analysis of the flow behaviors during the absorption of the fluid flow through the renal tubule and purification of blood through an artificial kidney.
基金Supported by a financial grant from CSIR,New Delhi,India,under Project No.03(1277)/13/EMR-Ⅱ
文摘This paper presents an investigation on the self-focusing/defocusing of chirped Gaussian laser beam in collisional plasma with linear absorption. We have derived the differential equation for the beam width parameter by using WKB and paraxial approximations and solved it numerically. The effect of chirp and other laser plasma parameters is seen on the behavior of beam width parameter with dimensionless distance of propagation. The results are discussed and presented graphically. Our simulation results show that the amplitude of oscillations decreases with the distance of propagation. Due to collisional frequency, the laser beam shows fast divergence which can be minimized by the introduction of chirp parameter. The chirp decreases the effect of defocusing and increases the ability of self-focusing of laser beam in collisional plasma.
基金supported by the National Natural Science Foundation of China(22090011,22378052)the Fundamental Research Funds for China Central Universities(DUT22LAB608 and DUT20RC(3)030)+1 种基金Liaoning Binhai Laboratory(LBLB-2023-03)Key R&D Program of Shandong Province(2021CXGC010308).
文摘In photolithography,shortening the exposure wavelength from ultraviolet to extreme ultraviolet(EUV,13.5 nm)and soft X-ray region in terms of beyond EUV(BEUV,6.X nm)and water window X-ray(WWX,2.2–4.4 nm)is expected to further miniaturize the technology node down to sub-5 nm level.However,the absorption ability of molecules in these ranges,especially WWX region,is unknown,which should be very important for the utilization of energy.Herein,the molar absorption cross sections of different elements at 2.4 nm of WWX were firstly calculated and compared with the wavelengths of 13.5 nm and 6.7 nm.Based on the absorption cross sections in these ranges and density estimation results from the density-functional theory calculation,the linear absorption coefficients of typical resist materials,including metal-oxy clusters,organic small molecules,polymers,and photoacid generators(PAGs),are evaluated.The analysis suggests that the Zn cluster has higher absorption in BEUV,whereas the Sn cluster has higher absorption in WWX.Doping PAGs with high EUV absorption atoms improves chemically amplified photoresist(CAR)polymer absorption performance.However,for WWX,it is necessary to introduce an absorption layer containing high WWX absorption elements such as Zr,Sn,and Hf to increase the WWX absorption.
基金Project supported by the Ministry of Higher Education and Scientific Research in Iraq,Ibnu Sina Institute and Physics Department of Universiti Teknologi Malaysia(UTM RUG Vote No.06-H14)
文摘Based on the Schr ¨odinger equation for envelope function in the effective mass approximation, linear and nonlinear optical absorption coefficients in a multi-subband lens quantum dot are investigated. The effects of quantum dot size on the interband and intraband transitions energy are also analyzed. The finite element method is used to calculate the eigenvalues and eigenfunctions. Strain and In-mole-fraction effects are also studied, and the results reveal that with the decrease of the In-mole fraction, the amplitudes of linear and nonlinear absorption coefficients increase. The present computed results show that the absorption coefficients of transitions between the first excited states are stronger than those of the ground states. In addition, it has been found that the quantum dot size affects the amplitudes and peak positions of linear and nonlinear absorption coefficients while the incident optical intensity strongly affects the nonlinear absorption coefficients.
基金Supported by the Deanship of Scientific Research of University of Dammam under Grant No 2015134
文摘In the framework of effective mass approximation, we theoretically investigate the electronic structure of the Si δ-doped InAIN/GaN single quantum well by solving numerically the coupled equations Schrodinger-Poisson self-consistently. The linear, nonlinear optical absorption coefficients and relative refractive index changes are calculated as functions of the doping concentration and its thickness. The obtained results show that the position and the amplitude of the linear and total optical absorption coefficients and the refractive index changes can be modified by varying the doping concentration and its thickness. In addition, it is found that the maximum of the optical absorption can be red-shifted or blue-shifted by varying the doping concentration. The obtained results are important for the design of various electronic components such as high-power FETs and infrared photonic devices.
文摘In this paper, a new model is proposed for manipulating the Kerr nonlinearity of right-hand circular probe light in a monolayer of graphene nanostructure. By using the density matrix equations and quantum optical approach, the third-order susceptibility of probe light is explored numerically. It is realized that the enhanced Kerr nonlinearity with zero linear absorption can be provided by selecting the appropriate quantities of controllable parameters, such as Rabi frequency and elliptical parameter of elliptical polarized coupling field. Our results may be useful applications in future all-optical system devices in nanostructures.
基金funded by the Henan Key Laboratory of Intelligent Manufacturing Equipment Integration for Superhard Materials(Grant No.JDKJ2022-01)the Key Lab of Modern Optical Technologies of Education Ministry of China,Soochow University。
文摘Graphene oxide(GO)is a two-dimensional carbon material with a graphene-like structure and many oxygen-containing functional groups,and in recent years from research into the unique optical properties of GO,GO-based composite materials formed by combining with other materials have shown improved overall performance.Reported here is an investigation of how doping with Ni,Fe,and Ag nanoparticles affects the linear and nonlinear optical properties of GO films.The morphology and structure of films of GO,GO with Ni nanoparticles,GO with Fe nanoparticles,and GO with Ag nanoparticles were studied by laser scanning confocal microscopy,SEM,energy dispersive spectroscopy,XRD,and Raman spectroscopy.UV-visible absorption spectra were used to study the optical absorption properties,and the optical band gaps of GO and the composites were calculated from those spectra via Tauc plots.The results show that the band gaps of GO films can be effectively regulated by metal nanoparticles,and so the properties of GO composites can be manipulated.The nonlinear optical properties of GO and GO-metal-nanoparticle composite films were studied by femtosecond laser Z-scanning.The results show that the femtosecond laser power can be tuned to the optical limiting behavior of GO.The strong synergistic coupling effect between metal nanoparticles and GO enhances the nonlinear absorption and nonlinear refraction of composite thin films.The nonlinear absorption coefficient of the composite thin films is improved significantly,and the optical limiting properties are excellent.GO-metal-nanoparticle composite materials have potential applications and advantages in improving optical absorption,band-gap control,and optical limiting.They can promote the expansion of GO composite materials in various practical applications and are candidates for good optical materials,opening the way to GO photonics.
基金Project supported by the National Natural Science Foundation of China(Grant No.10947004)the Jiangsu Government Scholarship for Overseas Studies
文摘For several types of the applied electric field configuration on the normal-zigzag black phosphorus nanoribbon(nZZ-BPNR)we investigate the band structure and the linear optical absorption spectrum,especially for the edge states and the corresponding low-energy absorption peaks.The obtained results show that the applied electric field can not only open another band gap at k=0.5 point,but also can change completely the spacial probabilities of edge states in the two edge bands.The strength of electric field can tune the two band gaps at the Γ point and 0.5 point.Further,one remarkable feature is that the forbidden transitionallowed.The lowest-excited-energy linear absorption peakfrom the transition between two edge bands at the Γ point.Finally,in comparison with the lowest-excited-energy peaks among various configurations,the second type of electric field configuration can move this peak blue-shift larger than other configurations.