Ulta-slow relaxation in discontinuous-film based electron glasses

Abstract

We present field effect measurements on discontinuous 2D thin films which are composed of a sub monolayer of nano-grains of Au, Ni, Ag or Al. Like other electron glasses these systems exhibit slow conductance relaxation and memory effects. However, unlike other systems, the discontinuous films exhibit a dramatic slowing down of the dynamics below a characteristic temperature $T^{\ast }$. $T^{\ast }$ is typically between 10-50K and is sample dependent. For $T<T^{\ast }$ the sample exhibits a few other peculiar features such as repeatable conductance fluctuations in millimeter size samples. We suggest that the enhanced system sluggishness is related to the current carrying network becoming very dilute in discontinuous films so that the system contains many parts which are electrically very weakly connected and the transport is dominated by very few weak links. This enables studying the glassy properties of the sample as it transitions from a macroscopic sample to a mesocopic sample, hence, the results provide new insight on the underlying physics of electron glasses.

4 pages, 4 figures

References in corpus (10)

• Electron Glass Dynamics
• Symmetrical field effect and slow electron relaxation in granular aluminium
• Relaxation dynamics in quantum electron-glasses
• Temperature and field dependence of Dynamics in the Electron-Glass
• Slow conductance relaxations; Distinguishing the Electron Glass from extrinsic mechanisms
• Nonlinearity exponents in lightly doped Conducting Polymers
• Coexistence of anomalous field effect and mesoscopic conductance fluctuations in granular aluminium
• The Electron-Glass in samples approaching the Mesoscopic regime
• Intrinsic electron-glassiness in strongly-localized Be films
• Determination of characteristic relaxation times and their significance in glassy disordered insulators

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• Nonequilibrium transport and Electron-Glass effects in thin GexTe films
• Observation of thermally activated glassiness and memory dip in a-NbSi insulating thin films
• Evidence for thermal activation in the glassy dynamics of insulating granular aluminum conductance
• Electron glass effects in amorphous NbSi films
• Zero bias anomaly in a two dimensional granular insulator
• Charging of highly resistive granular metal films
• Electron glass signatures up to room temperature in disordered insulators
• Anomalous thermal activation of the electron glass dynamics in a-InOx and granular aluminum
• Weak localization and universal conductance fluctuations in large area twisted bilayer graphene