YbRh2Si2:: Spin fluctuations in the vicinity of a quantum critical point at low magnetic field -: art. no. 107202
YbRh2Si2:: Spin fluctuations in the vicinity of a quantum critical point at low magnetic field -: art. no. 107202
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DOI：
10.1103/physrevlett.89.107202
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发表时间：
2002-09-02
影响因子：
8.6
通讯作者：
Steglich, F
中科院分区：
文献类型：
--
作者：
Ishida, K;Okamoto, K;Steglich, F
我们报道了对YbRh2Si2排列单晶的Si-29 NMR研究，显示出量子临界点（QCP: T-N—>）的行为特征。Si的奈特位移K和核自旋-晶格弛豫率1/T-1与外场H有很强的依赖性，特别是在5 kOe以下。在该测量中使用的最低H (h接近1.5 kOe)，发现1/T1T继续增加到50 mK，而K保持恒定，并在200 mK以下保持较大的量级。这一结果强烈表明，在H=0.5 kOe附近的QCP附近，具有有限q向量的反铁磁涨落与q=0自旋涨落竞争。
We report a Si-29 NMR study on aligned single crystals of YbRh2Si2 which shows behavior characteristic of a quantum critical point (QCP: T-N-->0). The Knight shift K and the nuclear spin-lattice relaxation rate 1/T-1 of Si show a strong dependence on the external field H, especially below 5 kOe. At the lowest H used in this measurement (Hsimilar to1.5 kOe), it was found that 1/T1T continues to increase down to 50 mK, whereas K stays constant with a large magnitude below 200 mK. This result strongly suggests the development of antiferromagnetic fluctuations with finite q vectors that compete with q=0 spin fluctuations in the vicinity of the QCP near H=0.5 kOe.