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Superconductivity and ferromagnetism in EuFe₂(As(1-x)P(x))₂
Guanghan Cao1, Shenggao Xu, Zhi Ren
1State Key Lab of Silicon Materials and Department of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China. ghcao@zju.edu.cn
Summary
Superconductivity and ferromagnetism coexist in EuFe₂(As(1-x)P(x))₂. This occurs due to iron 3d electrons and ordered Eu 4f moments, showing high transition temperatures and broad coexistence ranges.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Magnetism
Background:
- Superconductivity and ferromagnetism are typically antagonistic phenomena.
- Their coexistence is rare and challenging to achieve experimentally.
- Understanding coexistence is key to novel electronic properties.
Purpose of the Study:
- To experimentally demonstrate the coexistence of superconductivity and ferromagnetism.
- To investigate the underlying mechanisms in EuFe₂(As(1-x)P(x))₂.
- To explore the properties of coexisting superconducting and magnetic states.
Main Methods:
- Synthesis and characterization of EuFe₂(As(1-x)P(x))₂ compounds.
- Experimental investigation of superconducting and magnetic properties.
- Analysis of electron behavior and magnetic interactions.
Main Results:
- Demonstrated coexistence of superconductivity and ferromagnetism for 0.2 ≤ x ≤ 0.4.
- Identified superconductivity linked to Fe 3d electrons.
- Ferromagnetism attributed to RKKY interactions of Eu 4f moments.
- Observed large saturated ferromagnetic moments and high, comparable transition temperatures.
- Found broad coexistence ranges in temperature and magnetic field.
Conclusions:
- The unusual coexistence is attributed to the robustness of superconductivity.
- The multi-orbital character of iron pnictides facilitates this phenomenon.
- This finding opens new avenues for exploring emergent quantum phenomena in correlated materials.
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