Optical conductivity of iron-based superconductors

Abstract

The new family of unconventional iron-based superconductors discovered in 2006 immediately relieved their copper-based high-temperature predecessors as the most actively studied superconducting compounds in the world. The experimental and theoretical effort made in order to unravel the mechanism of superconductivity in these materials has been overwhelming. Although our understanding of their microscopic properties has been improving steadily, the pairing mechanism giving rise to superconducting transition temperatures up to 55 K remains elusive. And yet the hope is strong that these materials, which possess a drastically different electronic structure but similarly high transition temperatures compared to the copper-based compounds, will shed essential new light onto the several-decade-old problem of unconventional superconductivity. In this work we review the current understanding of the itinerant-charge-carrier dynamics in the iron-based superconductors and parent compounds largely based on the optical-conductivity data the community has gleaned over the past seven years using such experimental techniques as reflectivity, ellipsometry, and terahertz transmission measurements and analyze the implications of these studies for the microscopic properties of the iron-based materials as well as the mechanism of superconductivity therein.

Author's version of the invited review published in J. Phys.: Condens. Matter. 33 pages, 21 figures

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Cited by in corpus (10)

• Superconducting Properties of the $s^{\pm }$-wave state: Fe-based superconductors
• Interaction-induced singular Fermi surface in a high-temperature oxypnictide superconductor
• Correlation, doping and interband effects on the optical conductivity of iron superconductors
• Polar State induced by Block-type Lattice Distortions in BaFe2Se3 with Quasi-One-Dimensional Ladder Structure
• Muon spin rotation and infrared spectroscopy study of magnetism and superconductivity in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Phase stability and large in-plane resistivity in the 112-type iron-based superconductor Ca${}_{1-x}$La${}_x$FeAs${}_2$
• Carrier localization due to local magnetic order induced by magnetic impurities in Ba(Fe${}_{1-x}$TM${}_x$)${}_2$As${}_2$ (TM = Mn and Cr) as seen via optical spectra
• Unfolding optical transition weights of impurity materials for first-principles LCAO electronic structure calculations
• Quasiparticle interference in multiband superconductors with strong coupling
• Unique properties of the optical activity in noncentrosymmetric superconductors: sum rule, missing area, and relation with the superconducting Edelstein effect