arXiv subjects

R. Cimino

Publications and source records attributed to R. Cimino.

21 records · Page 2Linked to original sources

arXiv2002

Novel aspects and strong correlation in the electronic structure of Sr$_2$FeMoO$_6$

We investigate the electronic structure of Sr$_2$FeMoO$_6$ combining photoemission spectroscopy with a wide range of photon energies and electronic structure calculations based on first-principle as well as model Hamiltonian approaches to reveal several interesting aspects. We find evidence for unusually strong Coulomb correlation effects both in the Fe 3$d$ and O 2$p$ states, with an enhanced manifestation in the majority spin channel. Additionally, O 2$p$ states exhibit a spin-splitting of nonmagnetic origin, which nevertheless is likely to have subtle influence on the stability of novel ferromagnetism of this compound.

cond-mat.str-el↗

arXiv2001

Electronic and Magnetic Structures of Sr2FeMoO6

We have investigated the electronic and magnetic structures of Sr2FeMoO6 employing site-specific direct probes, namely x-ray absorption spectroscopy with linearly and circularly polarized photons. In contrast to some previous suggestions, the results clearly establish that Fe is in the formal trivalent state in this compound. With the help of circularly polarized light, it is unambiguously shown that the moment at the Mo sites is below the limit of detection (< 0.25mu_B), resolving a previous controversy. We also show that the decrease of the observed moment in magnetization measurements from the theoretically expected value is driven by the presence of mis-site disorder between Fe and Mo sites.

cond-mat.str-el↗

arXiv2001

Electronic structure of Ca$_{1-x}$Sr$_x$VO$_3$: a tale of two energy-scales

We investigate the electronic structure of Ca$_{1-x}$Sr$_x$VO$_3$ using photoemission spectroscopy. Core level spectra establish an electronic phase separation at the surface, leading to distinctly different surface electronic structure compared to the bulk. Analysis of the photoemission spectra of this system allowed us to separate the surface and bulk contributions. These results help us to understand properties related to two vastly differing energy-scales, namely the low energy-scale of thermal excitations (~$k_{B}T$) and the high-energy scale related to Coulomb and other electronic interactions.

cond-mat.str-el↗