Observation of successive phase transitions in Kagome lattice antiferromagnets RFe(3)(OH)(6)(SO4)(2) [R=NH4, Na, K]

被引：25

作者：

Maegawa, S ^{[1
]}

Nishiyama, M ^{[1
]}

Tanaka, N ^{[1
]}

Oyamada, A ^{[1
]}

Takano, M ^{[1
]}

机构：

[1] KYOTO UNIV, CHEM RES INST, UJI, KYOTO 611, JAPAN

来源：

JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN | 1996年 / 65卷 / 09期

关键词：

antiferromagnet; jarosite; Kagome lattice; frustration; successive phase transitions; susceptibility; NMR;

D O I：

10.1143/JPSJ.65.2776

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Successive magnetic phase transitions were found in the Kagome lattice antiferromagnets RFe(3)(OH)(6)(SO4)(2) [R = NH4, Na, K]. The temperature dependence of the susceptibility has two cusps around 60 K for each compound. The X-ray diffraction patterns and the quadrupole resonance spectra show that the transitions are not caused by a structural change. The presence of these transitions was confirmed by NMR experiments. The NMR spectra show the development of magnetic ordering below the upper transition temperature. Ln the low-temperature phase the nuclear magnetization does not relax exponentially, which may suggest a domain structure of 120 degrees spin structure due to degeneracy on the Kagome lattice. The successive transitions may be caused by a small Ising-like anisotropy in the Heisenberg antiferromagnet.

引用

页码：2776 / 2778

页数：3

共 16 条

[11] STATISTICS OF KAGOME LATTICE [J].