The soliton perturbations for the combined Korteweg de Vries and modified Korteweg de Vries(KdV-MKdV)equation are studied.The first-order effects of perturbation on a soliton,namely both the slow time-dependence of th...The soliton perturbations for the combined Korteweg de Vries and modified Korteweg de Vries(KdV-MKdV)equation are studied.The first-order effects of perturbation on a soliton,namely both the slow time-dependence of the soliton parameters and the first-order correction are derived through constructing the appropriate Green's function.展开更多
We numerically study the intrinsic localized vibrational modes in a diatomic chain with different masses and alternating force constants between nearest neighbors.This model simulates a row of atoms in the<111>d...We numerically study the intrinsic localized vibrational modes in a diatomic chain with different masses and alternating force constants between nearest neighbors.This model simulates a row of atoms in the<111>direction of sphalerite-structure crystal.We found that the harmonic and quartic anharmonic terms in the nearest-neighbor interaction potential produce the intrinsic localized modes with frequencies above the optical branch or in the gap of the linear spectrum,the distribution patterns of atom amplitudes are asymmetry with a form of quasi-even-or quasi-odd-parity,and the inclusion of cubic term in the potential lowers the frequencies of the modes and introduces static displacements for the atoms.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.19775013.
文摘The soliton perturbations for the combined Korteweg de Vries and modified Korteweg de Vries(KdV-MKdV)equation are studied.The first-order effects of perturbation on a soliton,namely both the slow time-dependence of the soliton parameters and the first-order correction are derived through constructing the appropriate Green's function.
基金Supported by the National Nature Science Foundation of China under Grant No.19975013by the Science Foundation of Hunan Education Commission under Grant No.301566.
文摘We numerically study the intrinsic localized vibrational modes in a diatomic chain with different masses and alternating force constants between nearest neighbors.This model simulates a row of atoms in the<111>direction of sphalerite-structure crystal.We found that the harmonic and quartic anharmonic terms in the nearest-neighbor interaction potential produce the intrinsic localized modes with frequencies above the optical branch or in the gap of the linear spectrum,the distribution patterns of atom amplitudes are asymmetry with a form of quasi-even-or quasi-odd-parity,and the inclusion of cubic term in the potential lowers the frequencies of the modes and introduces static displacements for the atoms.
