Coulomb Drag at the Onset of Anderson Insulators

Abstract

It is shown that the Coulomb drag between two identical layers in the Anderson insulting state indicates a striking difference between the Mott and Efros-Shklovskii (ES) insulators. In the former, the trans-resistance ${\rho }_t$ is monotonically increasing with the localization length $\xi$; in the latter, the presence of a Coulomb gap leads to an opposite result: ${\rho }_t$ is enhanced with a decreasing $\xi$, with the same exponential factor as the single layer resistivity. This distinction reflects the relatively pronounced role of excited density fluctuations in the ES state, implied by the enhancement in the rate of hopping processes at low frequencies. The magnitude of drag is estimated for typical experimental parameters in the different cases. It is concluded that a measurement of drag can be used to distinguish between interacting and non-interacting insulating state.

15 pages, revtex

References in corpus (5)

• Electric field scaling at a B=0 metal-insulator transition in two dimensions
• Magneto-Coulomb drag: interplay of electron--electron interactions and Landau quantization
• Coulomb drag in compressible quantum Hall states
• Logarithmic Temperature Dependence of Conductivity at Half Filled Landau Level
• Spin-Orbit Assisted Variable-Range Hopping in Strong Magnetic Fields

Cited by in corpus (7)

• Electron-drag effects in coupled electron systems
• Coulomb Drag in Coherent Mesoscopic Systems
• Coulomb Drag as a Probe of the Nature of Compressible States in a Magnetic Field
• Coulomb Drag for Strongly Localized Electrons: Pumping Mechanism
• Effective Drag Between Strongly Inhomogeneous Layers: Exact Results and Applications
• Investigating superconductor-insulator transition in thin films using drag resistance:Theoretical analysis of a proposed experiment
• Theoretical Analysis of Drag Resistance in Amorphous Thin Films Exhibiting Superconductor-Insulator-Transition