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Modeling the antiferromagnetic phase in iron pnictides: weakly ordered state.
E Kaneshita1, T Morinari, T Tohyama
1Yukawa Institute for Theoretical Physics, Kyoto University, Kyoto 606-8502, Japan.
Physical Review Letters
|April 7, 2010
Summary
We studied iron pnictides
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Antiferromagnetic iron pnictides exhibit complex electronic properties.
- Understanding their behavior is crucial for developing new electronic materials.
Purpose of the Study:
- To investigate the electronic states in the antiferromagnetic phase of iron pnictides.
- To analyze the optical conductivity and interlayer magnetoresistance.
Main Methods:
- Mean-field calculations of optical conductivity.
- Utilizing a five-band model.
Main Results:
- A five-band model reproduced excitation spectra with multipeak structures at low energies below the Néel temperature.
- An almost temperature-independent high-energy structure was observed.
- Characteristic field dependence of interlayer magnetoresistance was predicted, reflecting the Fermi surface.
Conclusions:
- The five-band model, despite a small magnetic moment, effectively describes the electronic excitations in antiferromagnetic iron pnictides.
- The predicted magnetoresistance offers insights into the Fermi surface properties.
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