TY - JOUR
T1 - Superconducting electronic state in optimally doped YBa2 Cu3 O7-δ observed with laser-excited angle-resolved photoemission spectroscopy
AU - Okawa, M.
AU - Ishizaka, K.
AU - Uchiyama, H.
AU - Tadatomo, H.
AU - Masui, T.
AU - Tajima, S.
AU - Wang, X. Y.
AU - Chen, C. T.
AU - Watanabe, S.
AU - Chainani, A.
AU - Saitoh, T.
AU - Shin, S.
PY - 2009/4/1
Y1 - 2009/4/1
N2 - Low-energy electronic structure of optimally doped YBa2 Cu3 O7-δ 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 ∼0.08-1 along (0,0) - (π,π) direction, significantly larger than Bi2 Sr2 CaCu2 O8+δ. 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 x2 - y2 -wave-like amplitude but exhibits a nonzero minimum of ∼12 meV along the (0,0) - (π,π) direction. Possible origins of such an unexpected "nodeless" gap behavior are discussed.
AB - Low-energy electronic structure of optimally doped YBa2 Cu3 O7-δ 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 ∼0.08-1 along (0,0) - (π,π) direction, significantly larger than Bi2 Sr2 CaCu2 O8+δ. 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 x2 - y2 -wave-like amplitude but exhibits a nonzero minimum of ∼12 meV along the (0,0) - (π,π) direction. Possible origins of such an unexpected "nodeless" gap behavior are discussed.
UR - http://www.scopus.com/inward/record.url?scp=66349102784&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=66349102784&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.79.144528
DO - 10.1103/PhysRevB.79.144528
M3 - Article
AN - SCOPUS:66349102784
SN - 1098-0121
VL - 79
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 14
M1 - 144528
ER -