Unusual electron-doping effects in Sr$_{2-x}$La$_x$FeMoO$_6$ observed by photoemission spectroscopy
| dc.creator | Saitoh, T. | |
| dc.creator | Nakatake, M. | |
| dc.creator | Nakajima, H. | |
| dc.creator | Morimoto, O. | |
| dc.creator | Kakizaki, A. | |
| dc.creator | Xu, Sh. | |
| dc.creator | Moritomo, Y. | |
| dc.creator | Hamada, N. | |
| dc.creator | Aiura, Y. | |
| dc.date | 2005-04-04 | |
| dc.date.accessioned | 2026-07-25T23:26:18Z | |
| dc.description | We have investigated the electronic structure of electron-doped Sr$_{2-x}$La$_x$FeMoO$_6$ ($x$=0.0 and 0.2) by photoemission spectroscopy and band-structure calculations within the local-density approximation+$U$ (LDA+$U$) scheme. A characteristic double-peak feature near the Fermi level ($E_{\rm F}$) has been observed in the valence-band photoemission spectra of both $x$=0.0 and 0.2 samples. A photon-energy dependence of the spectra in the Mo 4$d$ Cooper minimum region compared with the band-structure calculations has shown that the first peak crossing $E_{\rm F}$ consists of the (Fe+Mo) $t_{2g\downarrow}$ states (feature A) and the second peak well below $E_{\rm F}$ is dominated by the Fe $e_{g\uparrow}$ states (feature B). Upon La substitution, the feature A moves away from $E_{\rm F}$ by $\sim$50 meV which is smaller than the prediction of our band theory, 112 meV. In addition, an intensity enhancement of $both$ A and B has been observed, although B is not crossing $E_{\rm F}$. Those two facts are apparently incompatible with the simple rigid-band shift due to electron doping. We point out that such phenomena can be understood in terms of the strong Hund's rule energy stabilization in the 3$d^5$ configuration at the Fe sites in this compound. From an observed band-narrowing, we have also deduced a mass enhancement of $\sim$2.5 with respect to the band theory, in good agreement with a specific heat measurement. | |
| dc.description | 6 pages, 5 figures. Accepted for publication in Phys. Rev. B | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0504066 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0504066 | |
| dc.identifier.uri | https://dspace.dare.co.zw/handle/123456789/98438 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.title | Unusual electron-doping effects in Sr$_{2-x}$La$_x$FeMoO$_6$ observed by photoemission spectroscopy | |
| dc.type | text |