TY - JOUR
T1 - Evidence for suppressed screening on the surface of high temperature La2-xSrxCuO4 and Nd2-xCexCuO4 superconductors
AU - Taguchi, M.
AU - Chainani, A.
AU - Horiba, K.
AU - Takata, Y.
AU - Yabashi, M.
AU - Tamasaku, K.
AU - Nishino, Y.
AU - Miwa, D.
AU - Ishikawa, T.
AU - Takeuchi, T.
AU - Yamamoto, K.
AU - Matsunami, M.
AU - Shin, S.
AU - Yokoya, T.
AU - Ikenaga, E.
AU - Kobayashi, K.
AU - Mochiku, T.
AU - Hirata, K.
AU - Hori, J.
AU - Ishii, K.
AU - Nakamura, F.
AU - Suzuki, T.
PY - 2005/10/21
Y1 - 2005/10/21
N2 - Hard x-ray photoemission spectroscopy (PES) of Cu core electronic states, with a probing depth of ∼60, is used to show that the Zhang-Rice singlet feature is present in La2CuO4 but is absent in Nd2CuO4. Hole and electron doping in La2-xSrxCuO4 (LSCO) and Nd2-xCexCuO4 (NCCO) result in new well-screened features which are missing in soft x-ray PES. Impurity Anderson model calculations establish screening from doped states as its origin, which is strongly suppressed within 15 of the surface. Complemented with x-ray absorption spectroscopy, the small chemical-potential shift in core levels (∼0.2eV) are shown to be consistent with modifications of valence and conduction band states spanning the band gap (∼1eV) upon hole and electron doping in LSCO and NCCO.
AB - Hard x-ray photoemission spectroscopy (PES) of Cu core electronic states, with a probing depth of ∼60, is used to show that the Zhang-Rice singlet feature is present in La2CuO4 but is absent in Nd2CuO4. Hole and electron doping in La2-xSrxCuO4 (LSCO) and Nd2-xCexCuO4 (NCCO) result in new well-screened features which are missing in soft x-ray PES. Impurity Anderson model calculations establish screening from doped states as its origin, which is strongly suppressed within 15 of the surface. Complemented with x-ray absorption spectroscopy, the small chemical-potential shift in core levels (∼0.2eV) are shown to be consistent with modifications of valence and conduction band states spanning the band gap (∼1eV) upon hole and electron doping in LSCO and NCCO.
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U2 - 10.1103/PhysRevLett.95.177002
DO - 10.1103/PhysRevLett.95.177002
M3 - Article
AN - SCOPUS:28844454697
SN - 0031-9007
VL - 95
JO - Physical Review Letters
JF - Physical Review Letters
IS - 17
M1 - 177002
ER -