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

Sugata Ray·Priya Mahadevan·Ashwani Kumar·D. D. Sarma·R. Cimino·M. Pedio·L. Ferrari·A. Pesci
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Abstract

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.

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Sugata Ray, Priya Mahadevan, Ashwani Kumar, D. D. Sarma, R. Cimino, M. Pedio, L. Ferrari, A. Pesci. 2002-12-18. Novel aspects and strong correlation in the electronic structure of Sr$_2$FeMoO$_6$. https://arxiv.org/abs/cond-mat/0212458

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