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Multigap superconductivity in the heavy-Fermion system CeCoIn5
G Seyfarth1, J P Brison, G Knebel
1CNRS, Néel Institute, 25 avenue des Martyrs, BP166, 38042 Grenoble Cedex 9, France.
Physical Review Letters
|September 4, 2008
Summary
New experiments on the heavy-fermion superconductor CeCoIn5 show no unpaired electrons and reveal complex multigap effects impacting its response to magnetic fields.
Area of Science:
- Condensed Matter Physics
- Superconductivity Research
- Quantum Materials
Background:
- Heavy-fermion superconductors like CeCoIn5 exhibit complex electronic properties.
- Previous studies suggested the presence of unpaired electrons in CeCoIn5.
Purpose of the Study:
- To investigate the electronic state of CeCoIn5 at very low temperatures.
- To clarify the role of band structure complexity in the superconducting properties of heavy fermions.
Main Methods:
- Performed precise thermal conductivity measurements on CeCoIn5.
- Experiments were conducted at temperatures as low as 10 millikelvin (mK).
Main Results:
- Ruled out the existence of unpaired electrons in CeCoIn5.
- Observed strong multigap superconducting effects.
- Identified a low critical field (Hc2S) for the small gap band.
Conclusions:
- The findings challenge previous interpretations regarding unpaired electrons.
- The results highlight the significant influence of heavy-fermion band structure on superconducting behavior under magnetic fields.
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