Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the li...Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the light of experimental studies of the local-order structure of these alloys. In case of Cu85.5Al14.5, change in the total residual electrical resistivity due to neutron-irradiation effects has been estimated by including contributions from the short-range order and static atomic displacement correction. Our results show a decrease in the residual resistivity in the irradiated Cu-Al solid solution as compared to the unirradiated sample. This is in accordance with the experimental results展开更多
We explore the excitonic effects in chiral graphene nanoribbons (cGNRs), whose edges are composed alternatively of armchair-edged and zigzag-edged segments. For cGNRs dominated by armchair edges, their energy gaps and...We explore the excitonic effects in chiral graphene nanoribbons (cGNRs), whose edges are composed alternatively of armchair-edged and zigzag-edged segments. For cGNRs dominated by armchair edges, their energy gaps and exciton energies decrease with increasing chirality angles, and they, as functions of widths, oscillate with the period of three, while the exciton binding energies do not have such distinct oscillation. On the other hand, for cGNRs dominated by zigzag edges, all the energy gaps, exciton energies, and exciton binding energies show oscillation properties with their widths, due to the interactions between the edge states localized at the opposite zigzag edges. In addition, the triplet excitons are energy degenerate when the electrons are spin-unpolarized, while the degeneracy split when the electrons are spin-polarized. All the studied cGNRs show strong excitonic effects with the exciton binding energies of hundreds of meV.展开更多
The bias dependence of radiation-induced narrow-width channel effects(RINCEs) in 65-nm n-type metal-oxidesemiconductor field-effect transistors(NMOSFETs) is investigated. The threshold voltage of the narrow-width6...The bias dependence of radiation-induced narrow-width channel effects(RINCEs) in 65-nm n-type metal-oxidesemiconductor field-effect transistors(NMOSFETs) is investigated. The threshold voltage of the narrow-width65 nm NMOSFET is negatively shifted by total ionizing dose irradiation, due to the RINCE. The experimental results show that the 65 nm narrow-channel NMOSFET has a larger threshold shift when the gate terminal is kept in the ground, which is contrary to the conclusion obtained in the old generation devices. Depending on the three-dimensional simulation, we conclude that electric field distribution alteration caused by shallow trench isolation scaling is responsible for the anomalous RINCE bias dependence in 65 nm technology.展开更多
A unified description of finite nuclei and equation of state of neutron stars presents both a major challenge and also opportunities for understanding nuclear interactions.Inspired by the Lee-Huang-Yang formula of har...A unified description of finite nuclei and equation of state of neutron stars presents both a major challenge and also opportunities for understanding nuclear interactions.Inspired by the Lee-Huang-Yang formula of hardsphere gases,we develop effective nuclear interactions with an additional high-order density dependent term.While the original Skyrme force SLy4 is widely used in studies of neutron stars,there are not satisfactory global descriptions of finite nuclei.The refitted SLy4' force can improve descriptions of finite nuclei but slightly reduces the radius of neutron star of 1.4 M_☉ with M_☉ being the solar mass.We find that the extended SLy4 force with a higher-order density dependence can properly describe properties of both finite nuclei and GW170817 binary neutron stars,including the mass-radius relation and the tidal deformability.This demonstrates the essential role of high-order density dependence at ultrahigh densities.Our work provides a unified and predictive model for neutron stars,as well as new insights for the future development of effective interactions.展开更多
The irreducible water saturation(Swir) is a significant parameter for relative permeability prediction and initial hydrocarbon reserves estimation.However,the complex pore structures of the tight rocks and multiple fa...The irreducible water saturation(Swir) is a significant parameter for relative permeability prediction and initial hydrocarbon reserves estimation.However,the complex pore structures of the tight rocks and multiple factors of the formation conditions make the parameter difficult to be accurately predicted by the conventional methods in tight gas reservoirs.In this study,a new model was derived to calculate Swir based on the capillary model and the fractal theory.The model incorporated different types of immobile water and considered the stress effect.The dead or stationary water(DSW) was considered in this model,which described the phenomena of water trapped in the dead-end pores due to detour flow and complex pore structures.The water film,stress effect and formation temperature were also considered in the proposed model.The results calculated by the proposed model are in a good agreement with the experimental data.This proves that for tight sandstone gas reservoirs the Swir calculated from the new model is more accurate.The irreducible water saturation calculated from the new model reveals that Swir is controlled by the critical capillary radius,DSW coefficient,effective stress and formation temperature.展开更多
Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvable onedimensional quantum systems with non-constant mass, involving their ordering ambiguities. This work extends the res...Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvable onedimensional quantum systems with non-constant mass, involving their ordering ambiguities. This work extends the results recently reported in the literature and clarifies the relation between physically acceptable effective mass Hamiltonians.展开更多
A series of Al=-(Alq3)l-x granular films is prepared on Si wafer with native oxide layer using co-evaporation technique. Large lateral photovoltaic effect (LPE) is observed, with an optimal LPV sensitivity of 75 m...A series of Al=-(Alq3)l-x granular films is prepared on Si wafer with native oxide layer using co-evaporation technique. Large lateral photovoltaic effect (LPE) is observed, with an optimal LPV sensitivity of 75 mV/mm in x=0.35 sample. The dependence of LPE on temperature and A1 composition is investigated, and the possible mechanism is discussed.展开更多
With the support by the National Natural Science Foundation of China,a study by the research group led by Prof.Luo Junwei(骆军委)from the Institute of Semiconductors,Chinese Academy of Sciences discovered a rapid tran...With the support by the National Natural Science Foundation of China,a study by the research group led by Prof.Luo Junwei(骆军委)from the Institute of Semiconductors,Chinese Academy of Sciences discovered a rapid transition of the hole Rashba effect from strong field dependence to saturation展开更多
The unique chemical mechanical, and thermodynamic properties of nanofluids make them a subject of great interest for scientists from all domains. Such fluids are of particular significance in biomedical engineering ow...The unique chemical mechanical, and thermodynamic properties of nanofluids make them a subject of great interest for scientists from all domains. Such fluids are of particular significance in biomedical engineering owing to their vast and novel applications in modern drug delivery systems; for example, mixed convective peristaltic flow of water-based nanofluids under the influence of an externally applied magnetic field is of particular significance. Hence, a lot of research has focused on peristalsis in the presence of velocity and thermal slip effects. An empirical relation for the effective viscosity of the nanofluid is proposed here for the first time. The viscosity of the nanofluid varies with temperature and nanoparticle volume fraction. Numerical simulation of the resulting nonlinear system of equations is presented for different quantities of interest. The results indicate that the maximum velocity and temperature of the copper-water nanofluid increase for larger variable viscosity parameter. The pressure gradient in the wider part of the channel is also found to increase as a function of the variable viscosity parameter. The variable viscosity parameter also influences the size of the trapped bolus. An increase in the nanoparticle volume fraction reduces the reflux phenomenon in a peristaltic flow.展开更多
The third harmonic generation(THG),linear and nonlinear optical absorption coefficients(OACs),and refractive index changes(RICs)are investigated in a Woods-Saxon quantum well(QW)modulated by the hydrostatic pressure a...The third harmonic generation(THG),linear and nonlinear optical absorption coefficients(OACs),and refractive index changes(RICs)are investigated in a Woods-Saxon quantum well(QW)modulated by the hydrostatic pressure and applied electric field.The effect of non-uniform aluminum doping(position-dependent effective mass(PDEM))on the mass of the system is discussed,and further to explore the influence of PDEM on the nonlinear THG,OACs,and RICs of the Woods-Saxon QW.These nonlinear optical properties above are obtained using the compact-density matrix formalism.The electron states in a Woods-Saxon QW under the constant effective mass(CEM)and PDEM are calculated by solving the Schr?dinger equation via the finite difference technique.The contributions from competing effects of the hydrostatic pressure and applied electric field to the nonlinear optical properties with CEM and PDEM are reported,as well as the comparison with each other.The observations reveal that the regulation of external fields and the influence of PDEM play an important role in the photoelectric properties of QW.展开更多
We report on the effects of the polarization-dependent loss (PDL) on the polarization-multiplexed system. The result shows that the PDL of 0.9 dB could cause 1-dB power penalty. Unlike PMD, the effect of PDL was not d...We report on the effects of the polarization-dependent loss (PDL) on the polarization-multiplexed system. The result shows that the PDL of 0.9 dB could cause 1-dB power penalty. Unlike PMD, the effect of PDL was not dependent on the transmission speed.展开更多
文摘Residual electrical resistivity due to short-range order has been calculated for Cu100-xAlx (x=9.13,13.56, 14.5 and 14.76 in at pct) alloys using pseudopotential approach, and the results have been discussed in the light of experimental studies of the local-order structure of these alloys. In case of Cu85.5Al14.5, change in the total residual electrical resistivity due to neutron-irradiation effects has been estimated by including contributions from the short-range order and static atomic displacement correction. Our results show a decrease in the residual resistivity in the irradiated Cu-Al solid solution as compared to the unirradiated sample. This is in accordance with the experimental results
基金Supported by the National Key Scientific Research Projects of China under Grant No 2015CB932400the National Natural Science Foundation of China under Grant Nos 11504158,61474059,and U1432129+1 种基金the Program for New Century Excellent Talents in University of Ministry of Education of China under Grant No NCET-11-1003the Jiangxi Provincial'Ganpo Talentes 555Projects'
文摘We explore the excitonic effects in chiral graphene nanoribbons (cGNRs), whose edges are composed alternatively of armchair-edged and zigzag-edged segments. For cGNRs dominated by armchair edges, their energy gaps and exciton energies decrease with increasing chirality angles, and they, as functions of widths, oscillate with the period of three, while the exciton binding energies do not have such distinct oscillation. On the other hand, for cGNRs dominated by zigzag edges, all the energy gaps, exciton energies, and exciton binding energies show oscillation properties with their widths, due to the interactions between the edge states localized at the opposite zigzag edges. In addition, the triplet excitons are energy degenerate when the electrons are spin-unpolarized, while the degeneracy split when the electrons are spin-polarized. All the studied cGNRs show strong excitonic effects with the exciton binding energies of hundreds of meV.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11605282,11505282 and U1532261the West Light Foundation of the Chinese Academy of Sciences under Grant No 2015-XBQN-B-15
文摘The bias dependence of radiation-induced narrow-width channel effects(RINCEs) in 65-nm n-type metal-oxidesemiconductor field-effect transistors(NMOSFETs) is investigated. The threshold voltage of the narrow-width65 nm NMOSFET is negatively shifted by total ionizing dose irradiation, due to the RINCE. The experimental results show that the 65 nm narrow-channel NMOSFET has a larger threshold shift when the gate terminal is kept in the ground, which is contrary to the conclusion obtained in the old generation devices. Depending on the three-dimensional simulation, we conclude that electric field distribution alteration caused by shallow trench isolation scaling is responsible for the anomalous RINCE bias dependence in 65 nm technology.
基金Supported by the National Key R&D Program of China (Grant No.2018YFA0404403)the National Natural Science Foundation of China (Grant Nos.11975032,11835001,11790325,and 11961141003)。
文摘A unified description of finite nuclei and equation of state of neutron stars presents both a major challenge and also opportunities for understanding nuclear interactions.Inspired by the Lee-Huang-Yang formula of hardsphere gases,we develop effective nuclear interactions with an additional high-order density dependent term.While the original Skyrme force SLy4 is widely used in studies of neutron stars,there are not satisfactory global descriptions of finite nuclei.The refitted SLy4' force can improve descriptions of finite nuclei but slightly reduces the radius of neutron star of 1.4 M_☉ with M_☉ being the solar mass.We find that the extended SLy4 force with a higher-order density dependence can properly describe properties of both finite nuclei and GW170817 binary neutron stars,including the mass-radius relation and the tidal deformability.This demonstrates the essential role of high-order density dependence at ultrahigh densities.Our work provides a unified and predictive model for neutron stars,as well as new insights for the future development of effective interactions.
基金supported by the National Science Foundation (51904324, 51674279, 51804328)the Major National Science and Technology Project (2017ZX05009-001, 2017ZX05072)+3 种基金the Key Research and Development Program (2018GSF116004)the China Postdoctoral Science Foundation (2019T120616)the Funding for Scientific Research of China University of Petroleum East China (YJ20170013)Graduate Innovative Engineering project (YCX2019023)。
文摘The irreducible water saturation(Swir) is a significant parameter for relative permeability prediction and initial hydrocarbon reserves estimation.However,the complex pore structures of the tight rocks and multiple factors of the formation conditions make the parameter difficult to be accurately predicted by the conventional methods in tight gas reservoirs.In this study,a new model was derived to calculate Swir based on the capillary model and the fractal theory.The model incorporated different types of immobile water and considered the stress effect.The dead or stationary water(DSW) was considered in this model,which described the phenomena of water trapped in the dead-end pores due to detour flow and complex pore structures.The water film,stress effect and formation temperature were also considered in the proposed model.The results calculated by the proposed model are in a good agreement with the experimental data.This proves that for tight sandstone gas reservoirs the Swir calculated from the new model is more accurate.The irreducible water saturation calculated from the new model reveals that Swir is controlled by the critical capillary radius,DSW coefficient,effective stress and formation temperature.
文摘Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvable onedimensional quantum systems with non-constant mass, involving their ordering ambiguities. This work extends the results recently reported in the literature and clarifies the relation between physically acceptable effective mass Hamiltonians.
基金supported by the National Natural Science Foundation of China under Grant No.61076093
文摘A series of Al=-(Alq3)l-x granular films is prepared on Si wafer with native oxide layer using co-evaporation technique. Large lateral photovoltaic effect (LPE) is observed, with an optimal LPV sensitivity of 75 mV/mm in x=0.35 sample. The dependence of LPE on temperature and A1 composition is investigated, and the possible mechanism is discussed.
文摘With the support by the National Natural Science Foundation of China,a study by the research group led by Prof.Luo Junwei(骆军委)from the Institute of Semiconductors,Chinese Academy of Sciences discovered a rapid transition of the hole Rashba effect from strong field dependence to saturation
文摘The unique chemical mechanical, and thermodynamic properties of nanofluids make them a subject of great interest for scientists from all domains. Such fluids are of particular significance in biomedical engineering owing to their vast and novel applications in modern drug delivery systems; for example, mixed convective peristaltic flow of water-based nanofluids under the influence of an externally applied magnetic field is of particular significance. Hence, a lot of research has focused on peristalsis in the presence of velocity and thermal slip effects. An empirical relation for the effective viscosity of the nanofluid is proposed here for the first time. The viscosity of the nanofluid varies with temperature and nanoparticle volume fraction. Numerical simulation of the resulting nonlinear system of equations is presented for different quantities of interest. The results indicate that the maximum velocity and temperature of the copper-water nanofluid increase for larger variable viscosity parameter. The pressure gradient in the wider part of the channel is also found to increase as a function of the variable viscosity parameter. The variable viscosity parameter also influences the size of the trapped bolus. An increase in the nanoparticle volume fraction reduces the reflux phenomenon in a peristaltic flow.
基金Project supported by the National Natural Science Foundations of China(No.51971193)。
文摘The third harmonic generation(THG),linear and nonlinear optical absorption coefficients(OACs),and refractive index changes(RICs)are investigated in a Woods-Saxon quantum well(QW)modulated by the hydrostatic pressure and applied electric field.The effect of non-uniform aluminum doping(position-dependent effective mass(PDEM))on the mass of the system is discussed,and further to explore the influence of PDEM on the nonlinear THG,OACs,and RICs of the Woods-Saxon QW.These nonlinear optical properties above are obtained using the compact-density matrix formalism.The electron states in a Woods-Saxon QW under the constant effective mass(CEM)and PDEM are calculated by solving the Schr?dinger equation via the finite difference technique.The contributions from competing effects of the hydrostatic pressure and applied electric field to the nonlinear optical properties with CEM and PDEM are reported,as well as the comparison with each other.The observations reveal that the regulation of external fields and the influence of PDEM play an important role in the photoelectric properties of QW.
文摘We report on the effects of the polarization-dependent loss (PDL) on the polarization-multiplexed system. The result shows that the PDL of 0.9 dB could cause 1-dB power penalty. Unlike PMD, the effect of PDL was not dependent on the transmission speed.