NMR study of single crystal YbRhSi

Kambe, Shinsaku  ; Tokunaga, Yo  ; Sakai, Hironori   ; Matsuda, Tatsuma; Haga, Yoshinori   ; Lapertot, G.*; Aoki, Dai*; Flouquet, J.*; Brison, J. P.*

We have made 52% Si isotope enriched high quality single crystal sample of YbRhSi. Since the natural abundance of Si is only 4%, we can improve S/N of NMR signal by 100 times using this enriched sample. Spin-lattice relaxation time T is measured. In this compound, the QCP is appeared at 0.66T for H//c, 0.06T for H//a. At first, measurements are performed at 7.2T in the Fermi-liquid state. A crossover to the Fermi-liquid state is observed below 6K for H//a as previous report. The behavior for H//c is different.