Spectral properties of transition metal pnictides and chalcogenides: Angle-resolved photoemission spectroscopy and dynamical mean-field theory

Abstract

Electronic Coulomb correlations lead to characteristic signatures in the spectroscopy of transition metal pnictides and chalcogenides: quasi-particle renormalizations, lifetime effects or incoherent badly metallic behavior above relatively low coherence temperatures are measures of many-body effects due to local Hubbard and Hund's couplings. We review and compare the results of angle-resolved photoemission spectroscopy experiments (ARPES) and of combined density functional dynamical mean field theory (DFT+DMFT) calculations. We emphasize the doping-dependence of the quasi-particle mass renormalization and coherence properties.

Angle-resolved spectroscopy study of Ni-based superconductorSrNi2As2

“…The small renormalization factor (1.1) indicates that the electronic correlations in SrNi 2 As 2 are much weaker than that in the Fe-based superconductors, in which the overall bandwidth is typically renormalized by a factor of 2 ∼ 5 [8,9]. In addition, we do not observe in SrNi 2 As 2 any indication of orbital-selectivity, which contrasts with the Fe-pnictide superconductors, for which the bands with d xy character are renormalized twice as much as the other bands [13].…”

“…Unlike the Fe-based family of superconductors, the parent compounds of the Ni-based superconductors do not show any magnetic ordering. While electronic correlations are responsible for a renormalization of the band structure of the Fe-based superconductors by a typical factor of 2∼5 [8,9], recent angleresolved photoemission spectroscopy study (ARPES) reported that the band dispersions are renormalized by a factor of 1∼2 in BaNi 2 P 2 [10] and by a factor of 1.4 in TlNi 2 Se 2 [11], suggesting weaker electronic correlations in the Ni-based superconductors. Since Hund's coupling is believed to play a significant role to tune the correlation strength in these materials, a systematic study and comparison is of importance.…”

Is BaCr2As2 symmetrical to BaFe2As2Richard1, Roekeghem2, Lv3 et al. 2017Phys. Rev. BSelf Cite193120View full textAdd to dashboardCite

“…The electronic correlations are widely believed to play a major role for unconventional superconductivity in the Fe-based superconductors [1]. It was established theoretically that the strength of the electronic correlations in these materials is tuned by the filling of the 3d shell in presence of a large Hund's coupling [2][3][4][5][6][7].…”

NaFe0.56Cu0.44As: A Pnictide Insulating Phase Induced by On-Site Coulomb Interaction

“…This could explain why the valence band near E F is only renormalized by a factor of  1.35 (Fig. 2e), which is much smaller than the renormalization factor in Fe-pnictide parent or holedoped superconducting Fe-pnictide compounds (typically  2 -4) [11,[25][26][27] whose Fe 3d orbitals are partially filled. In Fig.…”