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ID 18781
本文ファイル
著者
Nimori, Shigeki
Sakita, Shigenobu
Nakamura, Fumihiko
Fujita, Toshizo
Hata, Hiroaki
抄録(英)
Using high-quality single crystals of La2-xSrxCuO4, Roman scattering spectra in the (c,c) geometry have been investigated in different Sr concentrations (x=0,0.1,0.113,0,15,0.22) and in the wide temperature region. It has been found that the apical oxygen vibration along the c axis shows the following anomalous behaviors in the dependences of the Sr concentration and temperature. With the increase of the Sr concentration, the peak intensity abruptly decreases from x=0 to 0.1 and its line shape becomes asymmetric. In the temperature dependence, its energy is almost constant or slightly decreases with decreasing temperature, and also its intensity decreases above 100 K universally in the doped samples. In addition, the background intensities increase with increasing x, except for x=0.113 at 6 K, where "1/8 problem" occurs. This increase shows that the background response is caused by an electronic excitation because the magnetic one is forbidden in the (c,c) spectra. The decrease of the background at x=0.113 at 6 K is understood by the formation of charge density wave. The asymmetric line shapes of the apical oxygen vibration are well explained by the Fano model, which is based on the interference effect between the phonon and electronic excitations. Furthermore, the abrupt decrease of the intensity from x=0 to 0.1 is also explained by the introduction of the electron-phonon interaction. The correlation between the obtained electron-phonon interaction and Tc has been found in the Sr-concentration dependence.
掲載誌名
Physical Review B - Condensed Matter and Materials Physics
62巻
6号
開始ページ
4142
終了ページ
4147
出版年月日
2000-08-01
出版者
American Physical Society
ISSN
1098-0121
NCID
出版者DOI
言語
英語
NII資源タイプ
学術雑誌論文
広大資料タイプ
学術雑誌論文
DCMIタイプ
text
フォーマット
application/pdf
著者版フラグ
publisher
権利情報
Copyright (c) 2000 American Physical Society.
関連情報URL
部局名
総合科学研究科
先端物質科学研究科