Charge Dynamics in 122 Iron-Based Superconductors

  • Aliaksei¬†Charnukha

Part of the Springer Theses book series (Springer Theses)

Table of contents

  1. Front Matter
    Pages i-xi
  2. Aliaksei Charnukha
    Pages 1-12
  3. Aliaksei Charnukha
    Pages 13-45
  4. Aliaksei Charnukha
    Pages 47-78
  5. Aliaksei Charnukha
    Pages 79-124
  6. Aliaksei Charnukha
    Pages 125-127
  7. Back Matter
    Pages 129-130

About this book


This thesis combines highly accurate optical spectroscopy data on the recently discovered iron-based high-temperature superconductors with an incisive theoretical analysis. Three outstanding results are reported: (1) The superconductivity-induced modification of the far-infrared conductivity of an iron
arsenide with minimal chemical disorder is quantitatively described by means of a strong-coupling theory for spin
fluctuation mediated Cooper pairing. The formalism developed in this thesis also describes prior spectroscopic data on more disordered compounds. (2) The same materials exhibit a sharp superconductivity-induced anomaly for photon energies around 2.5 eV, two orders of magnitude larger than the superconducting energy gap. The author provides a qualitative interpretation of this unprecedented observation, which is based on the multiband nature of the superconducting state. (3) The thesis also develops a comprehensive description of a superconducting, yet optically transparent iron chalcogenide compound. The author shows that this highly unusual behavior can be explained as a result of the nanoscopic coexistence of insulating and superconducting phases, and he uses a combination of two complementary experimental methods - scanning near-field optical microscopy and low-energy muon spin rotation - to directly image the phase coexistence and quantitatively determine the phase composition. These data have important implications for the interpretation of data from other
experimental probes.


Arsenides Broadband Spectroscopic Ellipsometry Chalcogenides Correlated Electron Systems Eliashberg Theory Selenides Solid-State Spectroscopy Superconductivity in Iron Pnictides

Authors and affiliations

  • Aliaksei¬†Charnukha
    • 1
  1. 1.Solid-State SpectroscopyMax Planck Institute for Solid State ResearchStuttgartGermany

Bibliographic information