다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

Weyl and Dirac semimetals are three-dimensional phases of matter with gapless electronic excitations that are protected by topology and symmetry. As three-dimensional analogs of graphene, they have generated much recent interest. Deep connections exist with particle physics models of relativistic chiral fermions, and, despite their gaplessness, to solid-state topological and Chern insulators. Their characteristic electronic properties lead to protected surface states and novel responses to applied electric and magnetic fields. The theoretical foundations of these phases, their proposed realizations in solid-state systems, and recent experiments on candidate materials as well as their relation to other states of matter are reviewed.

Weyl and Dirac semimetals in three-dimensional solids

Electronic excitations lie at the origin of most of the commonly measured spectra. However, the first-principles computation of excited states requires a larger effort than ground-state calculations, which can be very efficiently carried out within density-functional theory. On the other hand, two theoretical and computational tools have come to prominence for the description of electronic excitations. One of them, many-body perturbation theory, is based on a set of Green’s-function equations, starting with a one-electron propagator and considering the electron-hole Green’s function for the response. Key ingredients are the electron’s self-energy S and the electron-hole interaction. A good approximation for S is obtained with Hedin’s GW approach, using density-functional theory as a zero-order solution. First-principles GW calculations for real systems have been successfully carried out since the 1980s. Similarly, the electron-hole interaction is well described by the Bethe-Salpeter equation, via a functional derivative of S. An alternative approach to calculating electronic excitations is the time-dependent density-functional theory (TDDFT), which offers the important practical advantage of a dependence on density rather than on multivariable Green’s functions. This approach leads to a screening equation similar to the Bethe-Salpeter one, but with a two-point, rather than a four-point, interaction kernel. At present, the simple adiabatic local-density approximation has given promising results for finite systems, but has significant deficiencies in the description of absorption spectra in solids, leading to wrong excitation energies, the absence of bound excitonic states, and appreciable distortions of the spectral line shapes. The search for improved TDDFT potentials and kernels is hence a subject of increasing interest. It can be addressed within the framework of many-body perturbation theory: in fact, both the Green’s functions and the TDDFT approaches profit from mutual insight. This review compares the theoretical and practical aspects of the two approaches and their specific numerical implementations, and presents an overview of accomplishments and work in progress.

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Electronic excitations: density-functional versus many-body Green's-function approaches

Magnetic skyrmions are particle-like nanometre-sized spin textures of topological origin found in several magnetic materials, and are characterized by a long lifetime. Skyrmions have been observed both by means of neutron scattering in momentum space and microscopy techniques in real space, and their properties include novel Hall effects, current-driven motion with ultralow current density and multiferroic behaviour. These properties can be understood from a unified viewpoint, namely the emergent electromagnetism associated with the non-coplanar spin structure of skyrmions. From this description, potential applications of skyrmions as information carriers in magnetic information storage and processing devices are envisaged.

Topological properties and dynamics of magnetic skyrmions

Holographically recorded, ion etched ruled gratings can be obtained for the varied line spacing plane grating (VPG) monochromator at the Photon Factory BL19B. A new holographic recording method makes it possible to manufacture VPGs with large varied line coefficients for reducing the aberration terms in the optical path function. The efficiency at higher photon energies and the quantity of stray light are improved in comparison with mechanically ruled gratings. The calculation shows that the much lower efficiency at higher photon energies is not intrinsic for saw-tooth type gratings. It seems to be caused instead by carbon contamination, radiation damage, deformation at manufacturing and so on. # 2001 Elsevier Science B.V. All rights reserved.

/pdf/holographically-recorded-ion-etched-varied-line-spacing-1efjo5434x.pdf

Holographically recorded ion-etched varied line spacing grating for a monochromator at the Photon Factory BL19B

http://link.springer.com/content/pdf/10.1007/978-3-642-59484-7_271.pdf

Electronic states of interface Al-2p core excitons in GaAs/AlAs/GaAs heterostructures

Nanoscale Surface Elemental Analysis by Synchrotron Radiation Based Scanning Tunneling Microscope

The isovalent-substituted iron pnictide compound SrFe2(As1−xPx)2 exhibits multiple evidence for nodal superconductivity via various experimental probes, such as the penetration depth, nuclear magnetic resonance and specific heat measurements. The direct identification of the nodal superconducting (SC) gap structure is challenging, partly because the presence of nodes is not protected by symmetry but instead caused by an accidental sign change of the order parameter, and also because of the three-dimensionality of the electronic structure. We have studied the SC gaps of SrFe2(As0.65P0.35)2 in three-dimensional momentum space by synchrotron and laser-based angle-resolved photoemission spectroscopy. The three hole Fermi surfaces (FSs) at the zone center have SC gaps with different magnitudes, whereas the SC gaps of the electron FSs at the zone corner are almost isotropic and kz-independent. As a possible nodal SC gap structure, we propose that the SC gap of the outer hole FS changes sign around the Z-X [(0, 0, 2π) − (π, π, 2π)] direction.

/pdf/band-dependent-superconducting-gap-in-srfe-2-as-0-65-p-0-35-1oxjwiiev1.pdf

Band-dependent superconducting gap in SrFe 2 (As 0.65 P 0.35 ) 2 studied by angle-resolved photoemission spectroscopy

Valence-band photoemission and S L X-ray emission spectroscopies have been performed for CuIr 2 S 4 in order to investigate the electronic structure of the valence band. A structure around 1 eV below the Fermi level in the photoemission spectrum consists of Ir 5d as well as S 3p by taking into account its photon-energy dependent intensity. The S L 2 , 3 emission spectrum also shows a structure around 1 eV below the Fermi level, indicating that the state around 1 eV has the d-like or s-like character. These results indicate that S 3p has contribution to the electronic states near the Fermi level to some extent, and that the hybridization of Ir 5d with S 3p is important in understanding the electronic property of CuIr 2 S 4 .

/pdf/valence-band-structure-of-cuir2s4-studied-by-photoemission-289v4ganoy.pdf

Shik Shin

Papers

Holographically recorded ion-etched varied line spacing grating for a monochromator at the Photon Factory BL19B

Electronic states of interface Al-2p core excitons in GaAs/AlAs/GaAs heterostructures

Nanoscale Surface Elemental Analysis by Synchrotron Radiation Based Scanning Tunneling Microscope

Band-dependent superconducting gap in SrFe 2 (As 0.65 P 0.35 ) 2 studied by angle-resolved photoemission spectroscopy

Valence-band structure of CuIr2S4 studied by photoemission and S L X-ray emission spectroscopies