Other Condensed Matter
The lattice distortion parameter $\delta \equiv c/a-\sqrt{8/3}$ has been calculated as a function of molar volume for the hcp phases of He, Ar, Kr and Xe. Results from both semi-empirical potentials and density functional theory are…
We fluidize a granular medium through localized stirring and probe the mechanical response of quiescent regions far away from the main flow. In these regions the material behaves like a liquid: high-density probes sink, low-density probes…
A finite one-dimensional microscopic model of a superfulid is presented. The model consists of interacting Bose particles with an additional impurity particle confined to a ring. Both semiclassical and exact quantum calculations reveal…
We solve in random-phase approximation the anisotropic Heisenberg model, including nearest and next-nearest neighbour interactions by calculating all Green's functions and pair correlation functions in a cumulant decoupling scheme. The…
We study in random-phase approximation the newly discovered supersolid phase of ${}^4$He and present in detail its finite temperature properties. ${}^4$He is described within a hard-core quantum lattice gas model, with nearest and…
The position-dependent exact-exchange energy per particle $\varepsilon_x(z)$ (defined as the interaction between a given electron at $z$ and its exact-exchange hole) at metal surfaces is investigated, by using either jellium slabs or the…
We investigate the newly discovered supersolid phase by solving in random-phase approximation the anisotropic Heisenberg model of the hard-core boson ${}^4$He lattice at zero temperature. We include nearest and next-nearest neighbor…
We determine the polarization of the bulk $^{13}$C nuclear spin system in diamond produced by interaction with optically oriented nitrogen-vacancy (NV-) defect centers. $^{13}$C nuclei are polarized into the higher energy Zeeman state with…
We report on lasing in rolled-up microtube resonators. Time-resolved studies on these semiconductor lasers containing GaAs quantum wells as optical gain material reveal particularly fast turn-on-times and short pulse emissions above the…
We propose a general formula for the melting temperature of metals in terms of electronic mass, electronic number, and nearest-neighbor lattice distance. We derive it from the instability of the transverse phonon in the solid phase, using…
We study the spatio-temporal pattern of the near-field intensity correlations generated by parametric scattering processes in a planar optical cavity. A generalized Bogolubov-de Gennes model is used to compute the second order field…
The adiabatic connection of density functional theory (DFT) for electronic systems is generalized here to negative values of the coupling strength $\alpha$ (with {\em attractive} electrons). In the extreme limit $\alpha\to-\infty$ a simple…
We have recently analyzed theoretically the main characteristics of the edge depolarizing electric field (EDEF), in the vicinity of a non-polar face of a pyroelectric. In this work we measured and characterized the EDEF, excited by a…
This letter reports cavity dumping of an electrostatic-accelerator-driven free-electron laser (FEL) while it is injection-locked to a frequency-stabilized 240 GHz solid-state source. Cavity dumping enhances the FEL output power by a factor…
We report integration of an InAs quantum well micro-Hall sensor with microfluidics and real-time detection of moving superparamagnetic beads for biological applications. The detected positive and negative signals correspond to beads moving…
Recent experiments have demonstrated a remarkable progress in implementing and use of the Particle Image Velocimetry (PIV) and particle tracking techniques for the study of turbulence in He4. However, an interpretation of the experimental…
We address the issue of interaction between zero-point vacancies in solid 4He as described within the shadow wave-function model. Applying the reversible-work method and taking into account finite-size effects, we obtain a zero-point…
High pressure behaviour of superhydrous phase B(HT) of Mg10Si3O14(OH)4 (Shy B) is investigated with the help of density functional theory based first principles calculations. In addition to the lattice parameters and equation of state, we…
A long wavelength optical lattice is generated in a two-level medium by low-frequency contrapropagating beams. Then a short wave length gap soliton generated by evanescent boundary instability (supratransmission) undergoes a dynamics shown…
We consider synchronization of coupled chaotic systems and propose an adaptive strategy that aims at evolving the strength of the coupling to achieve stability of the synchronized evolution. We test this idea in a simple configuration in…