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Andreev reflection in nodal-line Weyl semimetal
1College of Physics and Electronic Engineering, Xinyang Normal University, Xinyang, 464000, People's Republic of China.
Summary
Quantum scattering in nodal-line Weyl semimetals reveals unique Andreev reflection behaviors. These findings, driven by material anisotropy, offer new insights into electron behavior at superconductor interfaces.
Area of Science:
- Condensed Matter Physics
- Quantum Materials Science
Background:
- Nodal-line Weyl semimetals exhibit unique electronic properties due to their band structure.
- Normal metal/superconductor (N/S) heterojunctions are crucial for studying quantum phenomena like Andreev reflection.
Purpose of the Study:
- To theoretically investigate quantum scattering in N/S heterojunctions based on nodal-line Weyl semimetals.
- To explore the impact of crystallographic anisotropy on Andreev reflection and tunneling conductance.
Main Methods:
- Utilizing the Bogoliubov-de Gennes equation to model the quantum scattering problem.
- Analyzing two distinct orientations of the superconducting interface relative to the crystalline axis.
Main Results:
- Perfect scattering via Klein-like Andreev reflection observed when the interface parallels the basal plane.
- Intra-mode retro-Andreev reflection (RAR) and inter-mode specular Andreev reflection (SAR) occur for perpendicular interfaces.
- Reentrant behavior in reflection coefficient and distinctive tunneling conductance features (sub-gap nonmonotonicity, zero bias conductances) were found.
Conclusions:
- The observed phenomena are attributed to the torus-like iso-energy surfaces unique to nodal-line Weyl semimetals.
- These scattering processes and conductance features provide experimental signatures to distinguish mode-resolved Andreev reflections.
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