9Be-NMR studies on anomalous superconducting phase diagram in UBe13

International Conference on Strongly Correlated Electron Systems 2016

Matsuno, Haruki^1 ; Morita, Kyohei^1 ; Kotegawa, Hisashi^1 ; Tou, Hideki^1 ; Haga, Yoshinori^2 ; Yamamoto, Etsuji^2 ; O'Nuki, Yoshichika^3

Department of Physics, Kobe University, Hyogo, Kobe

675-8501, Japan^1

Advanced Science Research Center, Japan Atomic Energy Agency, Tokai

319-1195, Japan^2

Faculty of Science, University of Ryukyus, Nishihara, Okinawa

903-0213, Japan^3

关键词: Crystal axis;    Knight shifts;    NMR measurements;    NMR spectrum;    NMR studies;    Spin singlets;    Superconducting phase diagrams;    Superconducting properties;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/807/5/052015/pdf
DOI  :  10.1088/1742-6596/807/5/052015

来源: IOP

【 摘 要 】

In order to clarify unusual superconducting properties, we have carried out9Be NMR measurements for a single crystal of UBe13with Tc≅ 0.85 K. The NMR spectra under 5 T parallel to [001] crystal axis show no change between Tc(H = 5 T) = 0.41 K and Ta(H = 5 T) = 0.35 K. Below Ta, 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, Kγ∼ 0.107 % estimated from electronic specific coefficient γe≅ 1000 mJ/(K2• mol). The origin of reduction of the Knight shift cannot be explained by spin singlet superconductivity.