相关论文: The Memory Effect in Electron Glasses
We discuss the history dependence and memory effects which are observed in the out-of-equilibrium conductivity of electron glasses. The experiments can be understood by assuming that the local density of states retains a memory of the…
The dielectric constant of amorphous solids at low temperatures is governed by the dynamics of tunneling systems, small groups of atoms which tunnel between quasi equivalent potential minima. Recent experiments showed that at temperatures…
We study the influence of various excitations on the anomalous field effect observed in insulating indium-oxide films. In conductance G versus gate-voltage Vg measurements one observes a characteristic cusp around the Vg at which the system…
We found that the current-voltage characteristics of the single-layer graphene field-effect transistors exhibit an intriguing feature - an abrupt change of the current near zero gate bias at elevated temperatures T > 500 K. The strength of…
We report on non equilibrium field effect in insulating amorphous NbSi thin films having different Nb contents and thicknesses. The hallmark of an electron glass, namely the logarithmic growth of a memory dip in conductance versus gate…
This paper describes the observation of non-equilibrium field effects at room temperature in four disordered insulating systems: granular Al, discontinuous Au, amorphous NbSi and amorphous InOx thin films. The use of wide enough gate…
A new kind of memory effect on low frequency dielectric measurements on plexiglass (PMMA) is described. These measurements show that cooling and heating the sample at constant rate give an hysteretic dependence on temperature of the…
We report on non-equilibrium transport features observed in experiments using three-dimensional amorphous indium-oxide films. It is demonstrated that all the features that characterize intrinsic electron-glasses which heretofore were seen…
At temperatures below 1 K, the capacitance of a glass sample changes due to the application of a DC field in accordance with A. Burins dipole gap theory. However, we now report that below 20 mK, during the first sweep cycle of the DC…
The standard model of glasses is an ensemble of two-level systems interacting with a thermal bath. The general origin of memory effects in this model is a quasi-stationary but non-equilibrium state of a single two-level system, which is…
We study the deviations from perfect memory in negative temperature cycle spin glass experiments. It is known that the a.c. susceptibility after the temperature is raised back to its initial value is superimposed to the reference isothermal…
We investigate theoretically the slow non-exponential relaxation dynamics of the electron glass out of equilibrium, where a sudden change in carrier density reveals interesting memory effects. The self-consistent model of the dynamics of…
When a spin glass is cooled down, a memory of the cooling process is imprinted in the spin structure. This memory can be disclosed in a continuous heating measurement of the ac-susceptibility. E.g., if a continuous cooling process is…
We perform electrical field effect measurements at 4 K on insulating granular aluminium thin films. When the samples size is reduced below 100 micrometers, reproducible and stable conductance fluctuations are seen as a function of the gate…
Low frequency dielectric measurements on plexiglass (PMMA) show that cooling and heating the sample at constant rate give an hysteretic dependence on temperature of the dielectric constant $\epsilon$. A temporary stop of cooling produces a…
The memory effect in a single crystal spin glass ($\mathrm{Cu}_{0.92}\mathrm{Mn}_{0.08}$) has been measured using \freq ac susceptibility techniques over a temperature range of $0.4 - 0.7 \, T_g$ and a model of the memory effect has been…
Slow conductance relaxations are observable in a many condensed matter systems. These are sometimes described as manifestations of a glassy phase. The underlying mechanisms responsible for the slow dynamics are often due to structural…
Low temperature properties of glasses are derived within a generalized tunneling model, considering the motion of charged particles on a closed path in a double-well potential. The presence of a magnetic induction field B violates the time…
We present new results obtained by field effect measurements on insulating granular Al thin films. First, reproducible and stable conductance fluctuations are seen in micron size samples as a function of gate voltage. The anomalous field…
The color memory effect is the non-abelian gauge theory analog of the gravitational memory effect, in which the passage of color radiation induces a net relative SU(3) color rotation of a pair of nearby quarks. It is proposed that this…