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Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Coulomb drag mechanisms in graphene
J C W Song1, D A Abanin, L S Levitov
1Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Nano Letters
|July 10, 2013
Summary
Anomalous Coulomb drag in graphene is explained by a new energy transport mechanism. This mechanism accounts for drag behavior near charge neutrality and magnetic field sensitivity, differing significantly from older models.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Phenomena
Background:
- Graphene exhibits anomalous Coulomb drag near charge neutrality, suggesting unexplored physics.
- Existing drag models do not fully explain observed phenomena in graphene.
Purpose of the Study:
- To elucidate the underlying physics of anomalous Coulomb drag in graphene.
- To propose and validate a new theoretical framework for Coulomb drag.
Main Methods:
- Theoretical modeling of interlayer energy transfer and its coupling to charge flow.
- Analysis of lateral heat currents and thermopower effects.
- Comparison of predictions from the new mechanism with experimental data.
Main Results:
- A novel energy transport mechanism explains anomalous Coulomb drag in graphene.
- This mechanism accounts for drag magnitude, sign, and magnetic field sensitivity near charge neutrality.
- Energy transport dominance leads to a universal drag value independent of interaction strength under realistic conditions.
Conclusions:
- The new energy transport mechanism provides a comprehensive explanation for anomalous Coulomb drag in graphene.
- This finding highlights the crucial role of energy transfer in charge dynamics.
- The results offer new insights into electron-electron interactions and transport phenomena in 2D materials.
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