摘要
Based on multiple scales method, we study the nonlinear properties of a new Fermi-Pasta-Ulam lattice model analytically. It is found that the lattice chain exhibits a novel nonlinear elementary excitation, i.e. a dark soliton. Moreover, the modulation depth of dark soliton is increasing as the anharmonic parameter increases.
基金
The project supported by National Natural Science Foundation of China under Grant No. 10674113, Foundation of New Century Excellent Talent under Grant No. NCET-060707, Natural Science Foundation of Hunan Province of China under Grant No. 06JJ50006, the Scientific Research Foundation of Education Bureau of Hunan Province of China under Grant Nos. 02C573 and 04A058
