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Superconductivity at 56 K in samarium-doped SrFeAsF.
1Hefei National Laboratory for Physical Science at Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China. Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
Summary
Substitution of samarium for strontium in SrFFeAs iron arsenide fluorides suppresses resistivity anomalies and induces superconductivity, reaching 56 K. This highlights potential for high-temperature superconductivity in these materials.
Area of Science:
- Solid State Chemistry
- Materials Science
- Condensed Matter Physics
Background:
- Iron arsenide fluorides with a ZrCuSiAs-type structure are a class of materials with interesting electronic properties.
- Understanding the relationship between chemical composition and superconducting behavior is crucial for discovering new superconductors.
Purpose of the Study:
- To investigate the effect of substituting rare earth metals (samarium) for alkaline earth metals (strontium) in SrFFeAs compounds.
- To explore the induction and characteristics of superconductivity in these modified iron arsenide fluoride systems.
Main Methods:
- Synthesis of Sr(1-x)Sm(x)FFeAs samples with a ZrCuSiAs-type structure.
- Characterization of the synthesized samples using electrical resistivity and magnetic susceptibility measurements.
Main Results:
- The substitution of samarium for strontium was found to suppress the anomaly observed in the resistivity measurements.
- Superconductivity was successfully induced in the Sr(1-x)Sm(x)FFeAs system.
- A superconducting transition temperature of 56 K was achieved for the nominal composition Sr(0.5)Sm(0.5)FFeAs.
Conclusions:
- Rare earth metal substitution in SrFFeAs is an effective strategy to induce superconductivity.
- The achieved superconducting transition temperature of 56 K is comparable to that found in oxypnictides with similar structures.
- Iron arsenide fluorides present a promising avenue for achieving high-temperature superconductivity.
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