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Ir doping-induced superconductivity in the SmFeAsO system.
Yong Liang Chen1, Cui Hua Cheng, Ya Jing Cui
1Key Laboratory of Advanced Technology of Materials (Ministry of Education of China), Superconductivity R&D Center (SRDC), Mail Stop 165, Southwest Jiaotong University, Chengdu, Sichuan 610031, China.
Journal of the American Chemical Society
|July 15, 2009
Summary
Iridium (Ir) doping in SmFeAsO induces superconductivity at 16 K. This 5d transition metal doping alters the As-Fe-As bond angle differently than charge-reservoir layer doping.
Area of Science:
- Solid State Physics
- Materials Science
- Superconductivity
Background:
- Samarium iron arsenide oxide (SmFeAsO) is a parent compound in the iron-based superconductor family.
- Understanding doping effects is crucial for tuning superconducting properties.
Purpose of the Study:
- To investigate the effect of 5d transition metal Iridium (Ir) doping on SmFeAsO.
- To explore the induction of superconductivity and its correlation with structural changes.
Main Methods:
- Chemical doping of Iridium (Ir) into the SmFeAsO lattice at approximately 15 atom %.
- Structural analysis to determine changes in bond angles, specifically the As-Fe-As bond angle (beta).
Main Results:
- Successful induction of superconductivity with a critical temperature (Tc) of 16 K.
- Observed a decrease in the As-Fe-As bond angle (beta) due to Ir doping.
- Demonstrated that Ir doping's effect on beta differs from doping in charge-reservoir layers.
Conclusions:
- 5d transition metal doping with Iridium is an effective strategy to induce superconductivity in SmFeAsO.
- The observed structural modification (decrease in beta) is a key factor in the induced superconductivity.
- Doping site significantly influences the structural response and superconducting properties.
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