Related papers: Electron Glass in a three-dimensional system
Transport measurements made on films of thallium-oxide (n-type semiconductor) are presented and discussed. The focus in this work is on the strongly-localized regime where charge transport is by variable-range-hopping. It is demonstrated…
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…
We study the dependence of the glassy properties of strongly localized indium-oxide films on the sample lateral dimensions. Characteristic mesoscopic effects such as reproducible conductance fluctuations (CF) are readily observable in gated…
We present a theory for the memory effect in electron glasses. In fast gate voltage sweeps it is manifested as a dip in the conductivity around the equilibration gate voltage. We show that this feature, also known as anomalous field effect,…
We present results of out--of-equilibrium transport measurements made on strongly-localized Beryllium films and demonstrate that these films exhibit all the earmarks of intrinsic electron-glasses. These include slow (logarithmic)…
We present a computer simulation study of a disordered two-dimensional system of localized interacting electrons at thermal equilibrium. It is shown that the configuration of occupied sites within the Coulomb gap persistently changes at…
The out-of-equilibrium excess conductance of electron-glasses typically relaxes with a logarithmic time-dependence. Here it is shown that the log(t) relaxation of a weakly-disordered amorphous indium-oxide films crosses-over asymptotically…
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 non-equilibrium relaxational properties of a three dimensional Coulomb glass model are investigated by kinetic Monte Carlo simulations. Our results suggest a transition from stationary to non-stationary dynamics at the equilibrium glass…
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…
We present a study of non-equilibrium phenomena observed in the electrical conductance of insulating granular aluminium thin films. An anomalous field effect and its slow relaxation are studied in some detail. The phenomenology is very…
In this work we investigate an unusual transport phenomenon observed in two-dimensional electron gas under integer quantum Hall effect conditions. Our calculations are based on the screening theory, using a semi-analytical model. The…
Long range interactions are relevant for a wide range of phenomena in physics where they often present a challenge to theory. In condensed matter, the interplay of Coulomb interaction and disorder remains largely an unsolved problem. In two…
We report on dynamic effects associated with thermally-annealing amorphous indium-oxide films. In this process the resistance of a given sample may decrease by several orders of magnitude at room-temperatures, while its amorphous structure…
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…
We examine in this work the role of disorder in contributing to the sluggish relaxation observed in intrinsic electron-glasses. Our approach is guided by several empirical observations: First and foremost, Anderson localization is a…
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…
A consequence of the disorder and Coulomb interaction competition is the electron-glass phase observed in several Anderson-insulators. The disorder in these systems, typically degenerate semiconductors, is stronger than the interaction,…
The relaxations of conductivity after a temporary change of carrier density n_s during the waiting time t_w have been studied in a strongly disordered two-dimensional electron system in Si. At low enough n_s < n_g (n_g - the glass…