9Be-NMR studies on anomalous superconducting phase diagram in UBe13
9Be-NMR studies on anomalous superconducting phase diagram in UBe13
复制标题
UBe13反常超导相图的9Be-NMR研究
DOI：
10.1088/1742-6596/807/5/052015
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Y. Onuki
中科院分区：
文献类型：
--
作者：
H. Matsuno;K. Morita;H. Kotegawa;H. Tou;Y. Haga;E. Yamamoto;Y. Onuki
为了阐明超导体的特殊性质，我们对Tc为0.85K的UBe 13单晶进行了9 Be NMR测量。平行于[0 0 1]晶轴的5 T核磁共振谱表明，Tc（H= 5 T）= 0.41K和Ta（H= 5 T）= 0.35K之间没有变化。然而，在Ta以下，观察到骑士位移的减少。Be（II）的Knight位移的减少量为~ 10.02%，远小于自旋部分的Knight位移，由电子比系数γ e ~ 1000 mJ/（K2· mol）估算出的K γ ~ 10.107%.骑士位移的减少的起源不能用自旋单重态超导来解释。
In order to clarify unusual superconducting properties, we have carried out 9 Be NMR measurements for a single crystal of UBe 13 with T c≅ 0.85 K. The NMR spectra under 5 T parallel to [001] crystal axis show no change between T c (H= 5 T)= 0.41 K and T a (H= 5 T)= 0.35 K. Below T a, however, the reduction of the Knight shift was observed. The reduction of the Knight shift of Be (II) is amount to∼ 0.02%, which is much smaller than spin part of the Knight shift, K γ∼ 0.107% estimated from electronic specific coefficient γ e≅ 1000 mJ/(K 2· mol). The origin of reduction of the Knight shift cannot be explained by spin singlet superconductivity.