Fermi surface of Ba{1-x}KxFe2As2 as probed by angle-resolved photoemission

V. B. Zabolotnyy; D. V. Evtushinsky; A. A. Kordyuk; D. S. Inosov; A. Koitzsch; A. V. Boris; G. L. Sun; C. T. Lin; M. Knupfer; B. Buechner; A. Varykhalov; R. Follath; S. V. Borisenko

doi:10.1016/j.physc.2009.03.043

arXiv · 0904.4337

Fermi surface of Ba{1-x}KxFe2As2 as probed by angle-resolved photoemission

V. B. Zabolotnyy·D. V. Evtushinsky·A. A. Kordyuk·D. S. Inosov·A. Koitzsch·A. V. Boris·G. L. Sun·C. T. Lin·M. Knupfer·B. Buechner·A. Varykhalov·R. Follath·S. V. Borisenko

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Abstract

Here we apply high resolution angle-resolved photoemission spectroscopy (ARPES) using a wide excitation energy range to probe the electronic structure and the Fermi surface topology of the Ba1-xKxFe2As2 (Tc = 32 K) superconductor. We find significant deviations in the low energy band structure from that predicted in calculations. A set of Fermi surface sheets with unexpected topology is detected at the Brillouin zone boundary. At the X-symmetry point the Fermi surface is formed by a shallow electron-like pocket surrounded by four hole-like pockets elongated in G-X and G-Y directions.

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V. B. Zabolotnyy, D. V. Evtushinsky, A. A. Kordyuk, D. S. Inosov, A. Koitzsch, A. V. Boris, G. L. Sun, C. T. Lin, M. Knupfer, B. Buechner, A. Varykhalov, R. Follath, S. V. Borisenko. 2009-04-28. Fermi surface of Ba{1-x}KxFe2As2 as probed by angle-resolved photoemission. https://doi.org/10.1016/j.physc.2009.03.043

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