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arXiv · 0901.1299

Fermi surface topology and low-lying quasiparticle structure of magnetically ordered Fe1+xTe

Y. Xia·D. Qian·L. Wray·D. Hsieh·G. F. Chen·J. L. Luo·N. L. Wang·M. Z. Hasan
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Abstract

We report the first photoemission study of Fe1+xTe - the host compound of the newly discovered iron-chalcogenide superconductors. Our results reveal a pair of nearly electron- hole compensated Fermi pockets, strong Fermi velocity renormalization and an absence of a spin-density-wave gap. A shadow hole pocket is observed at the "X"-point of the Brillouin zone which is consistent with a long-range ordered magneto-structural groundstate. No signature of Fermi surface nesting instability associated with Q= pi(1/2, 1/2) is observed. Our results collectively reveal that the Fe1+xTe series is dramatically different from the undoped phases of the high Tc pnictides and likely harbor unusual mechanism for superconductivity and quantum magnetic order.

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Y. Xia, D. Qian, L. Wray, D. Hsieh, G. F. Chen, J. L. Luo, N. L. Wang, M. Z. Hasan. 2009-01-09. Fermi surface topology and low-lying quasiparticle structure of magnetically ordered Fe1+xTe. https://doi.org/10.1103/physrevlett.103.037002

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