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Published on: December 29, 2016
Quantum criticality in the iron pnictides and chalcogenides
1Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, CA 90095, USA. abrahams@physics.ucla.edu
Summary
Quantum criticality may drive superconductivity in iron pnictides. Research explores accessing this magnetic quantum critical point using phosphorus substitution, with emerging experimental evidence supporting its existence and implications for iron-based superconductors.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Materials
Background:
- Superconductivity in iron pnictides and chalcogenides is observed near antiferromagnetic phases.
- The role of quantum criticality in these materials remains an open question.
- Understanding this relationship is key to developing new superconductors.
Purpose of the Study:
- To review theoretical work predicting a magnetic quantum critical point in iron pnictides.
- To discuss experimental evidence supporting the existence of this quantum critical point.
- To explore the implications of quantum criticality for iron-based superconducting materials.
Main Methods:
- Theoretical modeling of electronic localization and itinerancy competition.
- Proposal of isoelectronic phosphorus (P) substitution for arsenic (As) in undoped iron pnictides.
- Compilation and analysis of emerging experimental data.
Main Results:
- Theoretical prediction of a magnetic quantum critical point driven by electronic phase competition.
- Demonstration of accessing this critical point via P substitution for As.
- Emerging experimental evidence corroborates the existence of the quantum critical point in tuned iron pnictides.
Conclusions:
- Quantum criticality plays a significant role in the physics of iron pnictides and chalcogenides.
- Isoelectronic tuning offers a viable route to probe and potentially control quantum critical phenomena.
- These findings advance the understanding of unconventional superconductivity in iron-based materials.
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