Magnetic Behavior of a Mott-Insulator YVO3
Magnetic Behavior of a Mott-Insulator YVO3
复制标题
莫特绝缘体 YVO3 的磁行为
DOI：
10.1143/jpsj.63.2857
复制
发表时间：
1994
影响因子：
1.7
通讯作者：
Y. Ueda
中科院分区：
文献类型：
--
作者：
H. Kawano;H. Yoshizawa;Y. Ueda
Y1-xCaxVO3是ABO3型假钙钛矿氧化物家族的一员，随着掺杂钙离子浓度x的变化，Y1-xCaxVO3呈现出绝缘体-金属的转变。用中子散射技术重新研究了母体化合物YVO_3的磁性结构。YVO3在Tn1=118K时有序，具有所谓的C型反铁磁结构，但在Tn2∼77K时，YVO3通过一级晶格扭曲转变为G型反铁磁结构。这些自旋结构不同于Zubkov等人早期的研究。(Sov.物理--JETP 39(1974)896)。在T=0K时，对磁性长程有序有贡献的静力矩外推小于1.6uB，这一值比S=1的局域自旋系统预期的2.0uB小了20%以上，表明Mott绝缘体YVO3中存在自旋涨落。
As one of the members of the ABO 3 -type pseudoperovskite oxide family, Y 1- x Ca x VO 3 exhibits an insulator-metal transition upon a change in the dopant calcium ion concentration x . We have reinvestigated the magnetic structure of the parent compound YVO 3 with use of the neutron scattering technique. YVO 3 orders at T N1 =118 K with the so-called C-type antiferromagnetic structure, but changes to the G-type antiferromagnetic structure at T N2 ∼77 K through a first order transition with lattice distortion. These spin structures differ from those of an early study by Zubkov et al . (Sov. Phys.-JETP 39 (1974) 896). The static moment which contributes to the magnetic long range order is extrapolated to be less than 1.6 µ B at T =0 K. This value of the static moment is more than 20% smaller than 2.0 µ B expected for a localized spin system with S =1, indicating the existence of spin fluctuations in a Mott insulator YVO 3 .