17 research outputs found
Superconducting electronic state in optimally doped YBa2Cu3O7-d observed with laser-excited angle-resolved photoemission spectroscopy
Low energy electronic structure of optimally doped YBa2Cu3O7-d is
investigated using laser-excited angle-resolved photoemission spectroscopy. The
surface state and the CuO chain band that usually overlap the CuO2 plane
derived bands are not detected, thus enabling a clear observation of the bulk
superconducting state. The observed bilayer splitting of the Fermi surface is
~0.08 angstrom^{-1} along the (0,0)-(pi,pi) direction, significantly larger
than Bi2Sr2CaCu2O8+d. The kink structure of the band dispersion reflecting the
renormalization effect at ~60 meV shows up similarly as in other hole-doped
cuprates. The momentum-dependence of the superconducting gap shows
d_{x^2-y^2}-wave like amplitude, but exhibits a nonzero minimum of ~12 meV
along the (0,0)-(pi,pi) direction. Possible origins of such an unexpected
"nodeless" gap behavior are discussed.Comment: 9 pages, 10 figures; revised version accepted for publication in
Phys. Rev.
Properties of GaN-based light-emitting diodes on patterned sapphire substrate coated with silver nanoparticles prepared by mask-free chemical etching
Study of defects in LED epitaxial layers grown on the optimized hemispherical patterned sapphire substrates
High performance Schottky UV detectors (265-100 nm) using n-Al0.5Ga0.5N on AlN epitaxial layer
Crossover between magnetic vortex attraction and repulsion in thin films of layered superconductors
Crossover between magnetic vortex attraction and repulsion in thin films of layered superconductors
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