Satoshi Heguri

High-quality three-dimensional nanoporous graphene.

We report three-dimensional (3D) nanoporous graphene with preserved 2D electronic properties, tunable pore sizes, and high electron mobility for electronic applications. The complex 3D network comprised of interconnected graphene retains a 2D coherent electron system of massless Dirac fermions. The transport properties of the nanoporous graphene show a semiconducting behavior and strong pore-size dependence, together with unique angular independence. The free-standing, large-scale nanoporous graphene with 2D electronic properties and high electron mobility holds great promise for practical applications in 3D electronic devices.

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

Structure and thermoelectric properties of the n-type clathrate Ba8Cu5.1Ge40.2Sn0.7

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Van der Waals epitaxial growth of topological insulator Bi2−xSbxTe3−ySey ultrathin nanoplate on electrically insulating fluorophlogopite mica

10

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

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Development of Spatial Inhomogeneity of Internal Magnetic Field Above Tc in Bi2Sr2Ca1−xYxCu2O8+δ Observed by Longitudinal-Field Muon Spin Relaxation

cm

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

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Rattler Site Selectivity and Covalency Effects in Type-I Clathrates

(VS)

Mobility spectrum analytical approach for intrinsic band picture of Ba(FeAs)2

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A Field-Directional Specific Heat Study on the Gap Structure of Overdoped Ba(Fe1-xCox)(2)As-2

as minority carriers.