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Updated: Jul 2, 2025
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
8.5K
Finite-momentum Cooper pairing in proximitized altermagnets.
Song-Bo Zhang1,2,3, Lun-Hui Hu4,5,6, Titus Neupert7
1Hefei National Laboratory, Hefei, Anhui, 230088, China. songbozhang@ustc.edu.cn.
Nature Communications
|February 27, 2024
Summary
This study reveals that altermagnetic materials can host Cooper pairs with momentum, even without net magnetization. This finding opens new avenues for unconventional superconductivity research and material applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Magnetism
Background:
- Finite-momentum Cooper pairing typically requires net magnetization.
- Altermagnetism presents a unique magnetic phase with anisotropic spin-splitting but zero net magnetization.
Purpose of the Study:
- Investigate Cooper pairing in metallic altermagnets interfaced with s-wave superconductors.
- Explore the emergence and properties of finite Cooper-pair momentum in altermagnetic systems.
Main Methods:
- Theoretical study of Cooper pairing in altermagnet-superconductor heterostructures.
- Analysis of the impact of altermagnetism's anisotropic spin-splitting on Cooper pairs.
Main Results:
- Cooper pairs acquire finite center-of-mass momentum in altermagnets, irrespective of net magnetization.
- Anomalous Cooper-pair momentum exhibits direction-dependent symmetric patterns.
- Observed unique phenomena include orientation-dependent order parameter oscillations and controllable 0-π Josephson supercurrent transitions.
Conclusions:
- Altermagnetism enables unconventional superconductivity without net magnetization.
- The findings suggest potential for novel superconducting devices utilizing materials like RuO2 and KRu4O8.
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