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arXiv · 1002.4947

LDA+DMFT Spectral Functions and Effective Electron Mass Enhancement in Superconductor LaFePO

S. L. Skornyakov·N. A. Skorikov·A. V. Lukoyanov·A. O. Shorikov·V. I. Anisimov
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Abstract

In this Letter we report the first LDA+DMFT results (method combining Local Density Approximation with Dynamical Mean-Field Theory) for spectral properties of superconductor LaFePO. Calculated {\bf k}-resolved spectral functions reproduce recent angle-resolved photoemission spectroscopy (ARPES) data [D. H. Lu {\it et al}., Nature {\bf 455}, 81 (2008)]. Obtained effective electron mass enhancement values $m^{*}/m\approx$ 1.9 -- 2.2 are in good agreement with infrared and optical studies [M. M. Qazilbash {\it et al}., Nature Phys. {\bf 5}, 647 (2009)], de Haas--van Alphen, electrical resistivity, and electronic specific heat measurements results, that unambiguously evidence for moderate correlations strength in LaFePO. Similar values of $m^{*}/m$ were found in the other Fe-based superconductors with substantially different superconducting transition temperatures. Thus, the dynamical correlation effects are essential in the Fe-based superconductors, but the strength of electronic correlations does not determine the value of superconducting transition temperature.

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S. L. Skornyakov, N. A. Skorikov, A. V. Lukoyanov, A. O. Shorikov, V. I. Anisimov. 2010-02-26. LDA+DMFT Spectral Functions and Effective Electron Mass Enhancement in Superconductor LaFePO. https://doi.org/10.1103/physrevb.81.174522

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