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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
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Coupled multiple-mode theory for s± pairing mechanism in iron based superconductors
M N Kiselev1, D V Efremov2, S L Drechsler2
1The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, I-34151 Trieste, Italy.
Scientific Reports
|November 30, 2016
Summary
We studied magnetic and superconducting interactions in iron pnictides. Fluctuation effects suppress magnetic transitions, while superconducting contributions nearly balance.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Unconventional superconductors, like iron pnictides, exhibit complex interplay between magnetic and superconducting properties.
- Understanding this interplay is crucial for developing novel superconducting materials.
Purpose of the Study:
- Investigate the coupling between magnetic (spin density wave) and superconducting phenomena in multi-band superconductors.
- Analyze the critical region near the tetracritical point where magnetic and superconducting transitions coincide.
Main Methods:
- Developed a dynamical mode-mode coupling theory using coupled Bethe-Salpeter equations.
- Constructed a Ginzburg-Landau functional incorporating superconducting (SC) and spin density wave (SDW) fluctuations.
Main Results:
- Fluctuation corrections were found to suppress the magnetic transition temperature.
- Intraband and interband fluctuation contributions in the superconducting channel demonstrated near compensation.
Conclusions:
- The study provides insights into the delicate balance of magnetic and superconducting fluctuations in unconventional superconductors.
- The findings contribute to a deeper understanding of the phase diagram and properties of iron pnictide superconductors.
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