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تسجيل مستخدم جديدFermi surface topology and low-lying quasiparticle structure of magnetically ordered Fe1+xTe
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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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We report the first photoemission study of Fe$_{1+x}$Te - the host compound of the newly discovered iron-chalcogenide superconductors (maximum T$_c$ $sim$ 27K). 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=($pi$/2, $pi$/2) is observed. Our results collectively reveal that the Fe$_{1+x}$Te series is dramatically different from the high T$_{c}$ pnictides and likely harbor unusual mechanism for superconductivity and magnetic order.
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