NMR and NQR studies on transition-metal arsenide superconductors LaRu2As2, KCa2Fe4As4F2, and A2Cr3As3

NMR and NQR studies on transition-metal arsenide superconductors LaRu₂As₂, KCa₂Fe₄As₄F₂, and A₂Cr₃As₃

Luo Jun^{1, ‡}, Wang Chunguang^{1, 2}, Wang Zhicheng³, Guo Qi¹, Yang Ji¹, Zhou Rui^{1, 4}, Matano K⁵, Oguchi T⁶, Ren Zhian^{1, 2}, Cao Guanghan³, Zheng Guo-Qing^{1, 2, 5, §}

(a) Crystal structure of KCa₂Fe₄As₄F₂. There are two types of As sites marked by dark red and pink, respectively. (b) Nuclear magnetic resonance spectrum of KCa₂Fe₄As₄F₂ at H₀ = 11.999 T and T = 33 K. The dark red arrow and pink arrow correspond to the satellite peaks of As1 site and As2 site, respectively. Insets: central peaks after zooming in. Temperature dependence of NQR spectrums of (c) As2 site and (d) As1 site.