Evidence of Strong Correlations and Coherence-Incoherence Crossover in the Iron Pnictide Superconductor KFe2As2
F. Hardy, A. E. Böhmer, D. Aoki, P. Burger, T. Wolf, P. Schweiss, R. Heid, P. Adelmann, Y. X. Yao, G. Kotliar, J. Schmalian, C. Meingast
DOI 10.1103/PhysRevLett.111.027002 · Physical Review Letters
Active bibliographic source — not scientific approval
Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.
Abstract
Using resistivity, heat-capacity, thermal-expansion, and susceptibility measurements we study the normal-state behavior of KFe2As2. Both the Sommerfeld coefficient (γ≈103 mJ mol−1 K−2) and the Pauli susceptibility (χ≈4×10−4) are strongly enhanced, which confirm the existence of heavy quasiparticles inferred from previous de Haas–van Alphen and angle-resolved photoemission spectroscopy experiments. We discuss this large enhancement using a Gutzwiller slave-boson mean-field calculation, which shows the proximity of KFe2As2 to an orbital-selective Mott transition. The temperature dependence of the magnetic susceptibility and the thermal expansion provide strong experimental evidence for the existence of a coherence-incoherence crossover, similar to what is found in heavy fermion and ruthenate compounds, due to Hund’s coupling between orbitals.
Source-reported materials — not catalogue approval
| Formula | Reported Tc (K) | Pressure (GPa) | Type |
|---|---|---|---|
| KFe2As2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 3.4 | Pressure not reported | unknown |
| Ba1-xKxFe2As2 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 38 | Pressure not reported | unknown |
Similar papers
Evidence of Strong Correlations and Coherence-Incoherence Crossover in the Iron Pnictide Superconductor KFe2As2
similarity 0.96F. Hardy et al. · 2013 · arXiv:1302.1696
Source status unknown — claims are unverified
Crossover from weak to strong pairing in unconventional superconductors
similarity 0.95D. S. Inosov et al.
Source status unknown — claims are unverified
Hydrostatic and uniaxial pressure dependence of superconducting transition temperature of KFe2As2 single crystals
similarity 0.95Sergey L. Bud'ko et al.
Source status unknown — claims are unverified
Pauli-Limited Multiband Superconductivity in KFe2As2
similarity 0.95D. A. Zocco et al.
Source status unknown — claims are unverified
Structural, electronic, and magnetic properties of the possible pnictide superconductor BaFeAs2
similarity 0.95Zisheng Gong et al.
Source status unknown — claims are unverified
Band Structure and Fermi Surface of an Extremely Overdoped Iron-Based Superconductor KFe2As2
similarity 0.95T. Sato et al.
Source status unknown — claims are unverified