Related papers: Electrical glassy behavior in granular aluminium t…
We have measured the low temperature electrical resistivity of Ag : Mn mesoscopic spin glasses prepared by ion implantation with a concentration of 700 ppm. As expected, we observe a clear maximum in the resistivity (T ) at a temperature in…
We perform equilibrium parallel-tempering simulations of the 3D Ising Edwards-Anderson spin glass in a field. A traditional analysis shows no signs of a phase transition. Yet, we encounter dramatic fluctuations in the behaviour of the…
We derive new general expressions for the fluctuating electromagnetic field outside a homogeneous material surface. The analysis is based on general results from the thermodynamics of irreversible processes, and requires no consideration of…
We analyze the validity of the fluctuation-dissipation theorem for slow relaxation systems in the context of mesoscopic nonequilibrium thermodynamics. We demonstrate that the violation arises as a natural consequence of the elimination of…
A system is glassy when the observation time is much smaller than the equilibration time. A unifying thermodynamic picture of the glassy state is presented. Slow configurational modes are in quasi-equilibrium at an effective temperature. It…
This chapter is aimed at studying the anomalous magnetic properties (glassy behaviour) observed at low temperatures in nanoparticles of ferrimagnetic oxides. This topic is discussed both from numerical results and experimental data.…
The effect of thermal fluctuations on a thin film magnetoresistive element has been calculated. The technique involves adding to the basic spin dynamics a general form of interaction with a thermal bath. For a general anisotropic magnetic…
We report on intrinsic time-dependent conductance fluctuations observed in mesoscopic AuFe spin glass wires. These dynamical fluctuations have a 1/f-like spectrum and appear below the measured spin glass freezing temperature of our samples.…
The distribution of resistance fluctuations of conducting thin films with granular structure near electrical breakdown is studied by numerical simulations. The film is modeled as a resistor network in a steady state determined by the…
We analyze fluctuation-dissipation relations in the Backgammon model: a system that displays glassy behavior at zero temperature due to the existence of entropy barriers. We study local and global fluctuation relations for the different…
Complex systems having metastable elements often demonstrate nearly log-time relaxations and a kind of aging: repeated stimuli weaken the system's relaxational response. Granular matter is known to exhibit a wealth of such behaviors, for…
Some of the properties of the low temperature vortex-glass phase of randomly-pinned flux lines in 1+1 dimensions are studied. The flux arrays are found to be sensitive to small changes in external parameters such as the magnetic field or…
We develop the Elastically Collective Nonlinear Langevin Equation theory to investigate, for the first time, glassy dynamics in capped metallic glass thin films. Finite-size effects on the spatial gradient of structural relaxation time and…
We show the existence of intermittent dynamics in one of the simplest model of a glassy system: the two-state model, which has been used to explain the origin of the violation of the fluctuation-dissipation theorem. The dynamics is analyzed…
We revisit the field effect procedure used to characterise the slow dynamics of glassy Anderson insulators. It is shown that in the slowest systems the procedure fails and the "characteristic" time values extracted are not intrinsic but…
In amorphous materials, groups of particles can rearrange locally into a new stable configuration. Such elementary excitations are key as they determine the response to external stresses, as well as to thermal and quantum fluctuations. Yet,…
Using the plasma model for the metal dielectric function we have calculated the electromagnetic fluctuation induced forces on a free standing metallic film in vacuum as a function of the film size and the plasma frequency. The force for…
We report on transport measurements in a thin film of the 2D misfit Cobaltite $Ca_{3}Co_{4}O_{9}$. Dc magnetoresistance measurements obey the modified variable range hopping law expected for a soft Coulomb gap. When the sample is cooled…
We consider effects of an externally applied electrostatic field on superconductivity, self-consistently within a BCS mean field model, for a clean 3D metal thin film. The electrostatic change in superconducting condensation energy scales…
Dynamic magnetic properties and ageing phenomena of the re-entrant ferromagnet (Fe0.20Ni0.80)75P16B6Al3 are investigated by time dependent zero field cooled magnetic relaxation, m (t), measurements. The influence of a temperature cycling…