Jpn. J. Appl. Phys. 33 (1994) pp. 6699-6705 |Next Article| |Table of Contents|
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Cu 2p Photoelectron and 2p 3/2-Valence-Valence Auger Electron Spectra of Cuprate Superconductors
Shigemi Kohiki,
Koichi Mizuno1,
Akira Enokihara1,
Shigenori Hayashi1,
Masahiro Sakai1,
Kentaro Setsune1,
Sei Fukushima2 and
Yohichi Gohshi3
Kochi National College of Technology, Monobe, Nangoku, Kochi 783
1Central Research Laboratories, Matsushita Electric Industrial Co., Ltd., Seika, Soraku, Kyoto 619-02
2National Institute for Research in Inorganic Materials, Science and Technology Agency, Namiki 1-1, Tsukuba, Ibaraki 305
3Faculry of Engineering, Universiry of Tokyo, Hongo, Bunkyo, Tokyo 113
(Received August 25, 1994; accepted for publication October 15, 1994)
We have observed many-body effects in both the Cu 2p photoelectron and 2p3/2- valence-valence
(L3VV) Auger electron spectra for thin films of Bi2Sr2Ca xCu1+ xO6+2 x (x=0, 1, 2),
La2- xSr xCuO4 (x=0, 0.13), and ErBa2Cu3O7- x, y (x<y).
We reviewed the relationship between the many-body effects and high-T c superconductivity
of cuprate superconductors. Enlargements of both intensity ratio and energy separation of
the |cd10L> to |cd9> lines in the
2p spectra corresponded with an increase of the mixing of |d8L> and
|d7> states in the L3VV spectra. Enlargement of the parameters of
many-body effects resulted from an increase in covalency of the Cu–O bond. An enlargement
of the transfer integral is required for realization of high-T c superconductivity
of Bi–Sr–Ca–Cu–O and La–Sr–Cu–O systems. The 90 K superconductivity in Er–Ba–Cu–O
and Y–Ba–Cu–O systems was realized by increasing the charge transfer energy.
URL:
http://jjap.jsap.jp/link?JJAP/33/6699/
DOI: 10.1143/JJAP.33.6699
References
- S. Kohiki, J. Kawai, S. Hayashi, H. Adachi, S. Hatta, K. Setsune and K. Wasa:
J. Appl. Phys. 68 (1990) 1229[AIP Scitation].
- K. Okada and A. Kotani: J. Phys. Soc. Jpn. 58 (1989) 2578.
- J. Ghijsen, L. H. Tjeng, J. van Elp, H. Eskes, J. Westernik, G. A. Sawatzky and M. T. Czyzyk:
Phys. Rev. B 38 (1988) 11322[APS].
- G. van der Laan, C. Westra, C. Hass and G. A. Sawatzky:
Phys. Rev. B 23 (1981) 4369[APS].
- J. B. Mann: Los Alamos Scientific Laboratory Report No. LASL-3690.
- D. E. Ramaker, N. H. Turner, J. S. Murday, L. E. Toth, M. Osofsky and F. L. Hutson:
Phys. Rev. B 36 (1987) 5672[APS].
- D. E. Ramaker: J. Electron Spectrosc. 52 (1990) 341.
- J. J. Yeh, I. Lindau, J. Z. Sun, K. Char, N. Missert, A. Kapitulnik, T. H. Geballe and M. R. Beasley:
Phys. Rev. B 42 (1990) 8044[APS].
- J. J. Yeh:
Phys. Rev. B 45 (1992) 10816[APS].
- C. N. R. Rao, A. K. Santra and D. D. Sarma:
Phys. Rev. B 45 (1992) 10814[APS].
- S. Kohiki, S. Hatta, K. Setsune, K. Wasa, M. Sakai, S. Fukushima and Y. Gohshi:
J. Appl. Phys. 70 (1991) 6945[AIP Scitation].
- C. N. R. Rao, R. Nagarajan, A. K. Ganguli, G. N. Subbanna and S. V. Bhat:
Phys. Rev. B 42 (1990) 6765[APS].
- S. Kohiki, K. Hirochi, H. Adachi, K. Setsune and K. Wasa:
Phys. Rev. B 39 (1989) 4695[APS].
- K. Mizuno, H. Higashino, K. Setsune and K. Wasa:
Appl. Phys. Lett. 56 (1990) 1469[AIP Scitation].
- T. Kamada, S. Hayashi, S. Kohiki, H. Adachi, M. Kitagawa, T. Hirao and K. Wasa:
Jpn. J. Appl. Phys. 29 (1990) L83[JSAP].
- S. Kohiki, T. Satoh, S. Hatta, K. Setsune, K. Wasa, Y. Higashi, S. Fukushima and Y. Gohshi: Mater. Lett. 9 (1990) 185.
- A. K. McMahan, R. M. Martin and S. Satpathy:
Phys. Rev. B 38 (1988) 6650[APS].
- S. Kohiki, S. Hayashi, H. Adachi, S. Hatta, K. Setsune and K. Wasa: J. Phys. Soc. Jpn. 58 (1989) 4139.
- K. Karlsson, O. Gunnarsson and O. Jepsen:
Phys. Rev. B 45 (1992) 7559[APS]. They performed self-consistent local density functional calculations using the linear muffin-tin orbital method of the Cu 2p binding energies for Cu1+, Cu2+ and Cu3+, respectively, in YBa2Cu3O6.5, and in Cu2O, CuO and NaCuO2. The energy difference between the monovalent and divalent states and that between the divalent and trivalent were 0.9 and 0.5 eV, respectively. The calculated Cu 2p chemical shift for the trivalent state relative to the divalent state is smaller than that observed experimentally (1.
4 eV) [P. Steiner, S. Hufner, V. Kinsinger, I. Sander, B. Siegwart, H. Schmitt, R. Schulz, S. Junk, G. Schwitzgebel, A. Gold, C. Politis, H. P. Muller, R. Hoppe, S. Kemmeler-Sack and C. Kunz, Z. Phys. B 69 (1988) 449[CrossRef]].
