Anisotropic superconducting gap in transuranium superconductor   PuRhGa$_{5}$: Ga NQR study on a single crystal
  ^{69,71}Ga NMR/NQR studies have been performed on a single crystal of the transuranium superconductor PuRhGa_{5} with Tc ~ 9 K. We have observed a ^{69}Ga NQR line at ~29.15 MHz, and assigned it to the $4i$ Ga site using the NMR results. The ^{69}Ga NQR spin-lattice relaxation rate 1/T_{1} shows no coherence peak just below Tc, but obeys a T^{3} behavior below Tc. This result strongly suggests that PuRhGa_{5} is an unconventional superconductor having an anisotropic superconducting gap. 
H. Sakai, Y. Tokunaga, T. Fujimoto, S. Kambe, R. E. Walstedt, H.   Yasuoka, D. Aoki, Y. Homma, E. Yamamoto, A. Nakamura, Y. ...