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Quantized Nonlinear Conductance in Ballistic Metals.
1Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
Physical Review Letters
|March 4, 2022
Summary
We introduce a new terminal conductance for D-dimensional Fermi gases, generalizing Landauer conductance. In 2D, this conductance is quantized and measures the Fermi sea
Area of Science:
- Condensed Matter Physics
- Quantum Transport
Background:
- The Landauer conductance formula is a cornerstone of quantum transport in one dimension.
- Generalizing quantum transport formalisms to higher dimensions presents significant theoretical challenges.
Purpose of the Study:
- To introduce a D+1 dimensional nonlinear frequency-dependent terminal conductance for characterizing D-dimensional Fermi gases.
- To generalize the concept of Landauer conductance to higher dimensions.
- To explore the physical implications and experimental feasibility of this new conductance measure.
Main Methods:
- Development of a nonlinear frequency-dependent terminal conductance theory.
- Analysis of a D-dimensional Fermi gas model.
- Investigation of a 2D ballistic conductor system.
Main Results:
- A generalized D+1 terminal conductance is introduced, characterizing D-dimensional Fermi gases.
- For a 2D ballistic conductor, the conductance is shown to be quantized.
- The quantized conductance in 2D is demonstrated to probe the Euler characteristic of the Fermi sea.
Conclusions:
- The proposed terminal conductance offers a novel way to characterize Fermi gases in higher dimensions.
- The quantization of conductance in 2D systems provides a direct link to topological properties (Euler characteristic).
- Experimental verification using 2D Dirac materials like graphene with a triple point contact geometry is proposed.
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