Fractional Conductance in Strongly Interacting 1D Systems

Area of Science:

• Condensed Matter Physics
• Quantum Transport

Background:

• Electron-electron interactions significantly influence quantum transport in low-dimensional systems.
• Time-reversal symmetry often dictates expected transport properties, but exceptions exist.

Purpose of the Study:

• Investigate conditions for fractional quantized conductance and shot noise in 1D systems.
• Explore the role of strong electron-electron interactions and Fermi momentum commensurability.
• Connect theoretical findings to experimental observations in confined electron gases.

Main Methods:

• Utilized Abelian bosonization to analyze the strongly interacting regime.
• Employed a generalization of Luther-Emery refermionization for finite temperature and length effects.
• Examined conditions for commensurability of Fermi momenta and interaction strengths.

Main Results:

• Identified scenarios leading to two-terminal fractional quantized conductance and shot noise.
• Demonstrated these phenomena can occur even when time-reversal symmetry is conserved.
• Found the 2/5(e^2/h) conductance fraction in multiple model configurations.
• Observed conductance returning to integer values at small energy scales.

Conclusions:

• Strong interactions and specific commensurability conditions are key to fractional transport.
• The model provides a theoretical basis for experimental observations of fractional conductance plateaus.
• Disorder plays a role in the observed transport phenomena at low energies.