Normal-state spin dynamics in the spin-triplet superconductor Sr 2 RuO 4
Normal-state spin dynamics in the spin-triplet superconductor Sr 2 RuO 4
复制标题
自旋三重态超导体Sr 2 RuO 4 中的正常态自旋动力学
DOI：
10.1103/physrevb.64.100501
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发表时间：
2001
影响因子：
3.7
通讯作者：
Y. Maeno
中科院分区：
文献类型：
--
作者：
K. Ishida;H. Mukuda;Y. Minami;Y. Kitaoka;Z. Mao;H. Fukazawa;Y. Maeno
本文在钌核磁共振、氧核磁共振和中子衍射（ND）测量的基础上，讨论了自旋三重态超导体${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$正常状态下的磁性。除了ND测量探测到的强不匹配反铁磁（IC-AFM）波动外，通过NMR和ND结果的比较表明，在高达500 K的宽温度范围内存在与q无关的波动。从Ru和O位核自旋晶格弛豫速率${1/T}_{1}$的各向异性来看，IC-AFM涨落具有各向异性，因此低频动态磁化率的面外分量${\ensuremath{\chi}}_{IC,out}^{\ensuremath{''}}(q,\ensuremath{\omega})$比面内分量$\ensuremath{\sim}3$大，${\ensuremath{\chi}}_{IC,in}^{\ensuremath{''}}(q,\ensuremath{\omega}).$这些磁涨落的独特特征暗示与自旋三重态超导的发生有一定的关系。
Magnetic properties in the normal state of spin-triplet superconductor ${\mathrm{Sr}}_{2}{\mathrm{RuO}}_{4}$ are discussed on the basis of Ru- and O-NMR and neutron-diffraction (ND) measurements reported so far. Besides strong incommensurate antiferromagnetic (IC-AFM) fluctuations probed by the ND measurements, it is shown that q-independent fluctuations are present over a wide temperature range up to 500 K from the comparison between NMR and ND results. From an anisotropy in the nuclear spin lattice relaxation rate ${1/T}_{1}$ at both the Ru and O sites, it was found that the IC-AFM fluctuations are anisotropic so that the out-of-plane component of low-frequency dynamical susceptibility, ${\ensuremath{\chi}}_{IC,out}^{\ensuremath{''}}(q,\ensuremath{\omega})$ is by a factor of $\ensuremath{\sim}3$ larger than the in-plane one, ${\ensuremath{\chi}}_{IC,in}^{\ensuremath{''}}(q,\ensuremath{\omega}).$ These unique characters in magnetic fluctuations are implied to have some relevance for the occurrence of spin-triplet superconductivity.