Evolution from incoherent to coherent electronic states and its implications to superconductivity in FeTe1-xSex

E. Ieki; K. Nakayama; Y. Miyata; T. Sato; H. Miao; N. Xu; X. -P. Wang; P. Zhang; T. Qian; P. Richard; Z. -J. Xu; J. S. Wen; G. D. Gu; H. Q. Luo; H. -H. Wen; H. Ding; T. Takahashi

doi:10.1103/physrevb.89.140506

arXiv · 1405.1172

Evolution from incoherent to coherent electronic states and its implications to superconductivity in FeTe1-xSex

E. Ieki·K. Nakayama·Y. Miyata·T. Sato·H. Miao·N. Xu·X. -P. Wang·P. Zhang·T. Qian·P. Richard·Z. -J. Xu·J. S. Wen·G. D. Gu·H. Q. Luo·H. -H. Wen·H. Ding·T. Takahashi

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Abstract

We have performed systematic angle-resolved photoemission spectroscopy (ARPES) of iron-chalcogenide superconductor FeTe1-xSex to elucidate the electronic states relevant to the superconductivity. While the Fermi-surface shape is nearly independent of x, we found that the ARPES spectral line shape shows prominent x dependence. A broad ARPES spectrum characterized by a small quasiparticle weight at x = 0, indicative of incoherent electronic states, becomes progressively sharper with increasing x, and a well-defined quasiparticle peak appears around x = 0.45 where bulk superconductivity is realized. The present result suggests the evolution from incoherent to coherent electronic states and its close relationship to the emergence of superconductivity.

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E. Ieki, K. Nakayama, Y. Miyata, T. Sato, H. Miao, N. Xu, X. -P. Wang, P. Zhang, T. Qian, P. Richard, Z. -J. Xu, J. S. Wen, G. D. Gu, H. Q. Luo, H. -H. Wen, H. Ding, T. Takahashi. 2014-05-06. Evolution from incoherent to coherent electronic states and its implications to superconductivity in FeTe1-xSex. https://doi.org/10.1103/physrevb.89.140506

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