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Enhanced quasiparticle heat conduction in the multigap superconductor Lu2Fe3Si5
1Department of Physics, Tokyo Institute of Technology, Meguro, Tokyo 152-8551, Japan.
Physical Review Letters
|April 8, 2011
Summary
This study investigated the iron-based superconductor Lu2Fe3Si5, revealing multigap superconductivity. Enhanced quasiparticle heat conduction was observed in the mixed state, suggesting unique electronic properties.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Superconductivity
Background:
- Iron-based superconductors are a key area of research due to their unique electronic properties.
- Understanding the superconducting mechanisms in these materials is crucial for technological applications.
- Lu2Fe3Si5 is an iron-based superconductor with a critical temperature (Tc) around 6 K.
Purpose of the Study:
- To investigate the thermal transport properties of Lu2Fe3Si5 at low temperatures.
- To confirm the presence of multigap superconductivity and analyze the superconducting gaps.
- To compare the quasiparticle heat conduction in Lu2Fe3Si5 with other superconductors like MgB2.
Main Methods:
- Performed thermal conductivity measurements on Lu2Fe3Si5 down to T(c)/120.
- Analyzed the field and temperature dependences of thermal conductivity.
- Interpreted the results based on the electronic band structure, particularly the Fe 3d-electron character.
Main Results:
- Confirmed multigap superconductivity in Lu2Fe3Si5 with fully opened gaps across the Fermi surfaces.
- Observed a remarkably enhanced quasiparticle heat conduction in the mixed state compared to MgB2.
- The findings suggest that the unequal contribution of Fe 3d-electrons to different bands influences the observed phenomena.
Conclusions:
- Lu2Fe3Si5 exhibits complex multigap superconductivity.
- The enhanced heat conduction in the mixed state highlights the role of electronic band structure in its superconducting behavior.
- Further research into the electronic structure of iron-based superconductors is warranted.
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