Kondo insulators

Collapse of the Gd3+ ESR fine structure throughout the coherent temperature of the Gd-doped Kondo Semiconductor CeFeVenegas1, Garcia2, García3 et al. 2016Phys. Rev. B80100View full textAdd to dashboardCite

“…Photoemission Spectroscopy on single crystals of 4 12 CeFe P [1,22] showed a strong mixed-valence behavior of Ce ions, with a three-peak structure for the 4f - which is near the trivalent case as the nominal valence (value of 3.14). In addition, the anomaly observed in the lattice parameter [3,27] and results from band structure calculations [23] are also compatible with an intermediate-valence for the Ce ions.…”

“…Since the system is undergoing a 'smooth' insulator-metal transition at about 150 K, the exchange interaction between 3 …”

“…Therefore, there are enough indicia to include in the simulation the effect of the FV of Ce ions on the 3 …”

“…Among the strongly correlated electron systems, several rare-earth compounds, known as hybridization gap semiconductors or Kondo-insulators/semiconductors, have recently attracted great interest [1][2][3][4][5][6][7][8][9][10][11]. Kondo-insulators belong to a class of strongly correlated materials that form a group of either nonmagnetic semiconductors with a narrow-gap or semimetals with tiny gaps.…”

“…Differently from heavy fermions systems, in Kondo-insulators the heavy-electron band is completely filled and the chemical potential falls in the middle of the hybridization gap (half-filling condition [12]). This semiconducting state manifests when the pseudogap straddles the Fermi energy, and is subjected to many-body renormalizations, leading to a T-dependent reduction of its magnitude [1,[3][4][5][6][7][8][9][10][11][13][14][15][16][17]. Among new and interesting compounds with properties being related to this model are Ce-based filled skutterudites compounds [18].…”