NMR study of carrier doping effects on spin gaps in the spin ladder Sr(14-x)A(x)Cu(24)O(41) (A=Ca,Y, and La)

被引：106

作者：

Kumagai, K ^{[1
]}

Tsuji, S ^{[1
]}

Kato, M ^{[1
]}

Koike, Y ^{[1
]}

机构：

[1] TOHOKU UNIV, FAC ENGN, DEPT APPL PHYS, SENDAI, MIYAGI 98077, JAPAN

来源：

PHYSICAL REVIEW LETTERS | 1997年 / 78卷 / 10期

关键词：

D O I：

10.1103/PhysRevLett.78.1992

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Carrier doping effects on spin dynamics in Sr(14-x)A(x)Cu(24)O(41) (A=Ca, Y, and La) are investigated by Cu NMR and NQR. The energy gaps in the spin excitation spectra (spin gap) are confirmed to be Delta=140 K for the CuO2 chain and Delta=470 K for the Cu2O3 ladder in Sr14Cu24O41. The spin gap for the ladder increases with the Y and La substitutions for Sr (up to x=3), while it decreases with increasing x in Sr14-xCaxCu24O41 and seems to collapse around x=13 of the Ca substitution. Hole-doping effects on the spin gaps for the ladder configuration an interpreted in terms of magnon and hole-depairing excitations for the spin S=1/2 ladder.

引用

页码：1992 / 1995

页数：4