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Updated: Jun 10, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Electron Viscosity and Device-Dependent Variability in Four-Probe Electrical Transport in Ultraclean Graphene
Richa P Madhogaria1, Aniket Majumdar1, Nishant Dahma1
1Department of Physics, Indian Institute of Science (IISc), Bangalore 560012, India.
Nano Letters
|June 8, 2026
Summary
This study investigates electron hydrodynamics in graphene field-effect transistors (FETs). Results show device variability due to scattering, but a new analysis method yields consistent transport parameters for understanding quantum fluid behavior.
Area of Science:
- Condensed Matter Physics
- Solid-State Physics
- Quantum Electronics
Background:
- Graphene exhibits properties of a relativistic quantum fluid, enabling solid-state analogues of quantum fluid phenomena.
- Previous studies on electron hydrodynamics in graphene used complex geometries, leading to device-dependent observations and questions about inherent signatures.
Purpose of the Study:
- To investigate electron hydrodynamics in ultraclean graphene field-effect transistors (FETs) using a standardized rectangular four-terminal architecture.
- To examine the influence of carrier density and temperature on electrical resistance variations.
- To develop a method for analyzing experimental data to extract reliable transport parameters.
Main Methods:
- Fabrication of multiple ultraclean graphene field-effect transistors (FETs) in a rectangular four-terminal configuration.
- Electrical transport measurements to analyze resistance variations with carrier density and temperature.
- Development and application of a phenomenological analysis method.
Main Results:
- Observed significant device-dependent variability in electrical resistance.
- Attributed variability to competing momentum-conserving and momentum-relaxing scattering mechanisms.
- Successfully extracted transport parameters consistent with theoretical predictions and prior experimental findings.
Conclusions:
- The standardized device architecture and analysis method help disentangle intrinsic electron hydrodynamic signatures from fabrication-specific effects.
- The findings contribute to a more robust understanding of electron hydrodynamics in graphene.
- The proposed phenomenological method offers a pathway for consistent analysis of viscous electron flow experiments.
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