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Orbital occupancy and charge doping in iron-based superconductors
Claudia Cantoni1, Jonathan E Mitchell, Andrew F May
1Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Advanced Materials (Deerfield Beach, Fla.)
|July 30, 2014
Summary
The study reveals that while ordered iron (Fe) magnetic moments hinder superconductivity, fluctuating Fe magnetic moments increase near optimal superconducting conditions. This finding is crucial for understanding iron-based superconductors.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid-State Chemistry
Background:
- Iron-based superconductors are a critical class of materials exhibiting complex electronic properties.
- Understanding the role of local magnetic moments in these materials is essential for advancing superconductivity research.
Purpose of the Study:
- To investigate the intrinsic local magnetic moment and orbital occupations of iron (Fe) in iron-based superconductors.
- To correlate these properties with the emergence and optimal conditions of superconductivity.
Main Methods:
- Utilizing aberration-corrected scanning transmission electron microscopy/electron energy loss spectroscopy (STEM/EELS).
- Employing local, real-space analysis to probe atomic-level magnetic and electronic properties.
Main Results:
- Successfully unveiled the intrinsic Fe local magnetic moment and Fe orbital occupations.
- Demonstrated that while ordered Fe moments suppress superconductivity, local, fluctuating Fe magnetic moments are enhanced near optimal superconductivity.
Conclusions:
- The local, fluctuating nature of Fe magnetic moments plays a vital role in achieving optimal superconductivity in these materials.
- Suppression of long-range magnetic order is necessary, but localized magnetic fluctuations are beneficial.
Keywords:
electron energy loss spectroscopy (EELS)iron-based superconductorslocal magnetic momentsscanning transmission electron microscopy (STEM)More Related Videos
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