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arXiv · 0912.3152

Strong electron correlations in the normal state of FeSe0.42Te0.58

A. Tamai·A. Y. Ganin·E. Rozbicki·J. Bacsa·W. Meevasana·P. D. C. King·M. Caffio·R. Schaub·S. Margadonna·K. Prassides·M. J. Rosseinsky·F. Baumberger
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Abstract

We investigate the normal state of the '11' iron-based superconductor FeSe0.42Te0.58 by angle resolved photoemission. Our data reveal a highly renormalized quasiparticle dispersion characteristic of a strongly correlated metal. We find sheet dependent effective carrier masses between ~ 3 - 16 m_e corresponding to a mass enhancement over band structure values of m*/m_band ~ 6 - 20. This is nearly an order of magnitude higher than the renormalization reported previously for iron-arsenide superconductors of the '1111' and '122' families but fully consistent with the bulk specific heat.

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A. Tamai, A. Y. Ganin, E. Rozbicki, J. Bacsa, W. Meevasana, P. D. C. King, M. Caffio, R. Schaub, S. Margadonna, K. Prassides, M. J. Rosseinsky, F. Baumberger. 2010-02-10. Strong electron correlations in the normal state of FeSe0.42Te0.58. https://doi.org/10.1103/physrevlett.104.097002

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