Spinning Solitons of a Modified Non-Linear Schroedinger equation

We study soliton solutions of a modified non-linear Schroedinger (MNLS) equation. Using an Ansatz for the time and azimuthal angle dependence previously considered in the studies of the spinning Q-balls, we construct multi-node solutions of MNLS as well as spinning generalisations.Comment: 8 Revtex pages, 5 ps figures; v2: minor change

Ratchet dynamics of large polarons in asymmetric diatomic molecular chains

We study the dynamics of large polarons in diatomic molecular chains, at zero temperature, under the influence of an external, periodic in time, electric field of zero mean value. We show that in asymmetric chains, i.e. chains with two different atoms per unit cell, a harmonic unbiased field causes a drift of such polarons. Such a drift current, known as the ratchet phenomenon, depends strongly on the parameters of the chain; in particular, on the extent of the anisotropy of the chain and on the size of the polaron. Moreover, the drift takes place only if the intensity and the period of the field exceed some critical values which also depend on the parameters of the chain. We show that this directed current of polarons is a complicated phenomenon. It takes place in dissipative systems with a broken spatial symmetry and is generated by the interplay between the Peierls–Nabarro barrier and the impact of the external field on the charged polarons. The dependence of the amplitude of the polaron oscillations, the size of the drift per period of the external field and the average velocity are determined as a function of the intensity of the field and of its frequency

Multi-soliton energy transport in anharmonic lattices

We demonstrate the existence of dynamically stable multihump solitary waves in polaron-type models describing interaction of envelope and lattice excitations. In comparison with the earlier theory of multihump optical solitons [see Phys. Rev. Lett. {\bf 83}, 296 (1999)], our analysis reveals a novel physical mechanism for the formation of stable multihump solitary waves in nonintegrable multi-component nonlinear models.Comment: 4 pages, 4 figure

Evidence for a Quasi-1D Topological-Excitation Liquid in Bi2212 by Tunneling Spectroscopy

Tunneling measurements have been carried out on heavily underdoped and slightly overdoped Bi2212 single crystals by using a break-junction technique. We find that in-plane tunneling spectra below Tc are the combination of incoherent part from the pseudogap and coherent quasiparticle peaks. There is a correlation between the magnitude of the pseudogap and the magnitude of the superconducting gap in Bi2212. We find that the quasiparticle conductance peaks are caused by condensed solitonlike excitations.Comment: Europysics Lett. (in press

Quasi-One-Dimensional Topological-Excitation Liquid in Bi2212 from Tunneling Spectroscopy

Tunneling measurements have been carried out on heavily underdoped, slightly overdoped and partially Ni-substituted Bi2212 single crystals by using a break-junction technique. We find that in-plane tunneling spectra below Tc are the combination of incoherent part from the pseudogap and coherent quasiparticle peaks. There is a clear correlation between the magnitude of the pseudogap and the magnitude of the superconducting gap in Bi2212. The analysis of the data suggests that the tunneling pseudogap in Bi2212 is predominantly a charge-density-wave gap on dynamical charge stripes. The tunneling characteristics corresponding to the quasiparticle peaks are in excellent agreement with theoretical predictions made for a quasi-one dimensional topological-excitation liquid. In addition, the analysis of data measured by different techniques shows that the phase coherence along the c-axis is established at Tc due to spin fluctuations in local antiferromagnetic domains of CuO2 planes.Comment: Supercond. Sci. Technol. (16 pages