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We study a physical system consisting of a Bose-Einstein condensate confined to a ring shaped lattice potential interrupted by three weak links. The system is assumed to be driven by an effective flux piercing the ring lattice. By employing path integral techniques, we explore the effective quantum dynamics of the system in a pure quantum phase dynamics regime. Moreover, the effects of the density's quantum fluctuations are studied through exact diagonalization analysis of the spectroscopy of the Bose-Hubbard model. We demonstrate that a clear two-level system emerges by tuning the magnetic flux at degeneracy. The lattice confinement, platform for the condensate, is realized experimentally employing a spatial light modulator., Accepted in New Journal of Physics

Effects of stereoregularity and crystallization mode on the amorphous phase dynamics are investigated for poly(lactic acid) PLA. An isothermal crystallization from the melt and a cold crystallization are imposed. For each PLA, the cold crystallization leads to the appearance of a less perfect crystalline phase and to an important rigid amorphous fraction RAF content (35%), although only 10% of RAF is generated after crystallization from the melt. Temperature Modulated Differential Scanning Calorimetry is used to determine the Cooperative Rearranging Regions (CRR) size at the glass transition temperature in the mobile amorphous phase MAP. It is shown that the CRR size in the MAP is not modified by the appearance and the spherulite growth. For the intra-spherulite MAP, a confining effect is evidenced, causing an amorphous phase thickness decrease during crystallization, and inducing a drastic CRR size reduction.

We report on the observation of the phase dynamics of interacting one-dimensional ultracold bosonic gases with two internal degrees of freedom. By controlling the non-linear atomic interactions close to a Feshbach resonance we are able to induce a phase diffusive many-body spin dynamics. We monitor this dynamical evolution by Ramsey interferometry, supplemented by a novel, many-body echo technique. We find that the time evolution of the system is well described by a Luttinger liquid initially prepared in a multimode squeezed state. Our approach allows us to probe the non-equilibrium evolution of one-dimensional many-body quantum systems., Comment: 4 pages, 3 figures Updated version, minor changes

A numerically exact quantum mechanical approach is proposed to evaluate thermal rate constants for systems in a model condensed phase environment. Employing the reactive flux correlation function formalism, the approach efficiently combines the multilayer multiconfiguration time-dependent Hartree theory with an importance sampling scheme for thermal distribution of the initial states. The performance of the method is illustrated by applications to two models of condensed phase dynamics: the donor-acceptor electron transfer model also known as the spin-boson model and a model for proton transfer reactions in the condensed phase.

We experimentally address the long-time dynamics of an artificially curved growth interface in directional solidification. Repetitive cell nucleations are found to appear in a disordered way but to eventually organize themselves coherently, at long times. This behavior is recovered by simulation of a nonlinear advection-diffusion model for the phase dynamics. The existence of a periodic attractor is shown by deriving a Liapunov functional for the cellular pattern organization on time ranges that include the singular events of cell nucleation.

We reconsider microscopic grounds for the electric field and for the phase dynamics and relaxation of CDW/SDW, mostly for pure systems. We suggest a transparent form dynamic and dissipative equations for the DW phase and for electric field. The approach is based on a helpful relation between a "generalized condensate density" and a complex dielectric susceptibility of intrinsic carriers. Separately for CDW and SDW we discuss the spectra and the attenuation for the TO and LO modes, the low frequency relaxation, the intrinsic nonlinear conductivity.