By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical res...By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical results indicate that the higher-order effects can badly distort self-similar parabolic pulse shape and optical spectrum, and at the same time the peak shift and oscillation appear, while the pulse still reveals highly linear chirp but grows into asymmetry. The influence of different higher-order effects on self-similar parabolic pulse propagation has been analysed. It shows that the self-steepening plays a more important role. We can manipulate the geometrical parameters of the microstructured fibre amplifier to gain a suitable dispersion and nonlinearity coefficient which will keep high-quality self-similar parabolic pulse propagation. These results are significant for the further study of self-similar parabolic pulse propagation.展开更多
Higher order multipole potentials and electrostatic screening effects are introduced to incorporate the dangling bonds on the surface of a metallic nanopaticle and to modify the coulomb like potential energy terms,res...Higher order multipole potentials and electrostatic screening effects are introduced to incorporate the dangling bonds on the surface of a metallic nanopaticle and to modify the coulomb like potential energy terms,respectively. The total interaction energy function for any metallic nanoparticle is represented in terms of two- and three-body potentials. The two-body part is described by dipole-dipole interaction potential,and in the three-body part,triple-dipole (DDD) and dipole-dipole-quadrupole(DDQ) terms are included.The size-dependent cohesive energy and bulk modulus are observed to decrease with decreasing sizes,a result which is in good agreement with the experimental values of Mo and W nanoparticles.展开更多
Previous studies presented the phase diagram induced by the disorder existing separately either in the higher-order topological states or in the topological trivial states, respectively. However, the influence of diso...Previous studies presented the phase diagram induced by the disorder existing separately either in the higher-order topological states or in the topological trivial states, respectively. However, the influence of disorder on the system with the coexistence of the higher-order topological states and other traditional topological states has not been investigated. In this paper, we investigate the disorder induced phase transition in the magnetic higher-order topological insulator. By using the convolutional neural network and non-commutative geometry methods, two independent phase diagrams are calculated.With the comparison between these two diagrams, a topological transition from the normal insulator to the Chern insulator is confirmed. Furthermore, the network based on eigenstate wavefunction studies also presents a transition between the higher-order topological insulator and the Chern insulator.展开更多
We discuss a new class of RSH braneworld cosmology exhibiting accelerated expansion and dominated byquintessence. It is explicitly demonstrated that the universe expansion history (transition from inflation to deceler...We discuss a new class of RSH braneworld cosmology exhibiting accelerated expansion and dominated byquintessence. It is explicitly demonstrated that the universe expansion history (transition from inflation to decelerationepoch to acceleration and effective quintessence era) may naturally occur in such unified theory for some classes of inversescalar potentials. Besides a decaying effective cosmological constant, the model incorporates an increasing black holemass, an increasing Maxwellian electrical charge with cosmic time and a time-dependent brane tension. The cosmologicalmodel exhibits several features of cosmological and astrophysical interest for both the early and late universe consistentwith recent observations, in particular the ones concerned with the gravitational constants, black holes masses andcharges and variation of the gauge coupling parameters with cosmic time. One interesting mark of the constructedmodel concerns the fact that a black hole mass surrounded by quintessence energy may increase with time even if thehorizon disappears.展开更多
A differential quadrature (DQ) method for orthotropic plates was proposed based on Reddy' s theory of plates with the effects of the higher-order transverse shear deformations. Wang-Bert's DQ approach was also...A differential quadrature (DQ) method for orthotropic plates was proposed based on Reddy' s theory of plates with the effects of the higher-order transverse shear deformations. Wang-Bert's DQ approach was also further extended to handle the boundary conditions of plates. The computational convergence was studied, and the numerical results were obtained for different grid spacings and compared with the existing results. The results show that the DQ method is fairly reliable and effective.展开更多
Based on Tai’ s high - order bidirectional associative memory ( HOBAM) and Stmposon’ s intraconnected BAM (IBAM) , two Improved models are first presented and discussed in this paper. The improved models not only re...Based on Tai’ s high - order bidirectional associative memory ( HOBAM) and Stmposon’ s intraconnected BAM (IBAM) , two Improved models are first presented and discussed in this paper. The improved models not only retain the advantages of both HOBAM and ISAM but overcome the shortcomings of Kosko’ s BAM also. Secondly their recall stabilities in synchronous and asyn-chronous update modes have been proven by defining corresponding energy functions which decrease as the re-call process proceeds such that the systems can ensure all the training pattern pairs to become local minima of the energy surfaces. Finally with signal - to - noise ratio (SNR) approach, we show that their storage capacities and error correction capabilities are better than that of the HOBAM.展开更多
The nonlinear theory of interaction between the q analogue of a single-mode field and a Ξ-type threelevel atom has been established. And the formal solution of the Schrodinger equation in the representation and its a...The nonlinear theory of interaction between the q analogue of a single-mode field and a Ξ-type threelevel atom has been established. And the formal solution of the Schrodinger equation in the representation and its average number are obtained. Then, the photon squeezing effects are studied through numerical calculation. The results show that the q deformation nonlinear action has a lot of influence on the quantum coherence and quantum properties. When q approaches 1, the theory reduces to the common linear theory.展开更多
基金Project supported by the National Science Foundation of Guangdong Province,China(Grant No04010397)
文摘By considering higher-order effects, the properties of self-similar parabolic pulses propagating in the microstructured fibre amplifier with a normal group-velocity dispersion have been investigated. The numerical results indicate that the higher-order effects can badly distort self-similar parabolic pulse shape and optical spectrum, and at the same time the peak shift and oscillation appear, while the pulse still reveals highly linear chirp but grows into asymmetry. The influence of different higher-order effects on self-similar parabolic pulse propagation has been analysed. It shows that the self-steepening plays a more important role. We can manipulate the geometrical parameters of the microstructured fibre amplifier to gain a suitable dispersion and nonlinearity coefficient which will keep high-quality self-similar parabolic pulse propagation. These results are significant for the further study of self-similar parabolic pulse propagation.
基金Supported by King Saud University,College of Science-Research Center,Project Number PHYS/2009/19
文摘Higher order multipole potentials and electrostatic screening effects are introduced to incorporate the dangling bonds on the surface of a metallic nanopaticle and to modify the coulomb like potential energy terms,respectively. The total interaction energy function for any metallic nanoparticle is represented in terms of two- and three-body potentials. The two-body part is described by dipole-dipole interaction potential,and in the three-body part,triple-dipole (DDD) and dipole-dipole-quadrupole(DDQ) terms are included.The size-dependent cohesive energy and bulk modulus are observed to decrease with decreasing sizes,a result which is in good agreement with the experimental values of Mo and W nanoparticles.
基金Project supported by the National Natural Science Foundation of China(Grant No.11822407)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘Previous studies presented the phase diagram induced by the disorder existing separately either in the higher-order topological states or in the topological trivial states, respectively. However, the influence of disorder on the system with the coexistence of the higher-order topological states and other traditional topological states has not been investigated. In this paper, we investigate the disorder induced phase transition in the magnetic higher-order topological insulator. By using the convolutional neural network and non-commutative geometry methods, two independent phase diagrams are calculated.With the comparison between these two diagrams, a topological transition from the normal insulator to the Chern insulator is confirmed. Furthermore, the network based on eigenstate wavefunction studies also presents a transition between the higher-order topological insulator and the Chern insulator.
文摘We discuss a new class of RSH braneworld cosmology exhibiting accelerated expansion and dominated byquintessence. It is explicitly demonstrated that the universe expansion history (transition from inflation to decelerationepoch to acceleration and effective quintessence era) may naturally occur in such unified theory for some classes of inversescalar potentials. Besides a decaying effective cosmological constant, the model incorporates an increasing black holemass, an increasing Maxwellian electrical charge with cosmic time and a time-dependent brane tension. The cosmologicalmodel exhibits several features of cosmological and astrophysical interest for both the early and late universe consistentwith recent observations, in particular the ones concerned with the gravitational constants, black holes masses andcharges and variation of the gauge coupling parameters with cosmic time. One interesting mark of the constructedmodel concerns the fact that a black hole mass surrounded by quintessence energy may increase with time even if thehorizon disappears.
基金key Project of the Municipal Commission of Science and Technology of Shanghai
文摘A differential quadrature (DQ) method for orthotropic plates was proposed based on Reddy' s theory of plates with the effects of the higher-order transverse shear deformations. Wang-Bert's DQ approach was also further extended to handle the boundary conditions of plates. The computational convergence was studied, and the numerical results were obtained for different grid spacings and compared with the existing results. The results show that the DQ method is fairly reliable and effective.
文摘Based on Tai’ s high - order bidirectional associative memory ( HOBAM) and Stmposon’ s intraconnected BAM (IBAM) , two Improved models are first presented and discussed in this paper. The improved models not only retain the advantages of both HOBAM and ISAM but overcome the shortcomings of Kosko’ s BAM also. Secondly their recall stabilities in synchronous and asyn-chronous update modes have been proven by defining corresponding energy functions which decrease as the re-call process proceeds such that the systems can ensure all the training pattern pairs to become local minima of the energy surfaces. Finally with signal - to - noise ratio (SNR) approach, we show that their storage capacities and error correction capabilities are better than that of the HOBAM.
文摘The nonlinear theory of interaction between the q analogue of a single-mode field and a Ξ-type threelevel atom has been established. And the formal solution of the Schrodinger equation in the representation and its average number are obtained. Then, the photon squeezing effects are studied through numerical calculation. The results show that the q deformation nonlinear action has a lot of influence on the quantum coherence and quantum properties. When q approaches 1, the theory reduces to the common linear theory.
