Takahiro Urata

Electric transport of a single-crystal iron chalcogenide FeSe superconductor: Evidence of symmetry-breakdown nematicity and additional ultrafast Dirac cone-like carriers

An SDW antiferromagnetic (SDW-AF) low temperature phase transition is generally observe and the AF spin fluctuations are considered to play an important role for the superconductivity paring mechanism in FeAs superconductors. However, a similar magnetic phase transition is not observed in FeSe superconductors, which has caused considerable discussion. We report on the intrinsic electronic states of FeSe as elucidated by transport measurements under magnetic fields using a high quality single crystal. A mobility spectrum analysis, an ab initio method that does not make assumptions on the transport parameters in a multicarrier system, provides very import and clear evidence that another hidden order, most likely the symmetry broken from the tetragonal C4 symmetry to the C2 symmetry nematicity associated with the selective d-orbital splitting, exists in the case of superconducting FeSe other than the AF magnetic order spin fluctuations. The intrinsic low temperature phase in FeSe is in the almost compensated semimetallic states but is additionally accompanied by Dirac cone like ultrafast electrons

Effects of strain on the electronic structure, superconductivity, and nematicity in FeSe studied by angle-resolved photoemission spectroscopy

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Coexistence of Dirac-cone states and superconductivity in iron pnictide Ba(Fe1−xRuxAs)2

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Superconductivity pairing mechanism from cobalt impurity doping in FeSe: Spin (s.+-.) or orbital (s++) fluctuation

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Enhanced superconducting transition temperature in hyper-interlayer-expanded FeSe despite the suppressed electronic nematic order and spin fluctuations

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Kondo-like mass enhancement of Dirac fermions in Ba(Fe1−xMnxAs)2

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Suppression of backward scattering of Dirac fermions in iron pnictides Ba(Fe1−xRuxAs)2

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Emergence of high-mobility minority holes in the electrical transport of theBa(Fe1−xMnxAs)2iron pnictides

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Reconstruction of band structure induced by electronic nematicity in an FeSe superconductor.

as minority carriers.

Nonmonotonic and anisotropic magnetoresistance effect in antiferromagnet CaMn2Bi2

One of central issues in iron-based superconductors is the role of structural change to the superconducting transition temperature (