Successive Magnetic Transitions In The Heavy-Fermion Superconductor Ce3ptin11 Studied By In-115 Nuclear Quadrupole Resonance

Nuclear quadrupole resonance (NQR) measurements were performed on the heavy-fermion superconductor Ce3PtIn11 with T-c = 0.32 K. The temperature dependence of both spin-lattice relaxation rate 1/T-1 and NQR spectra evidences the occurrence of two successive magnetic transitions with T-N1 similar or equal to 2.2 K and T-N2 similar or equal to 2.0 K. In successive magnetic transitions, even though the magnetic moment at the Ce(2) site plays a major role, the magnetic moment at the Ce(1) site also contributes to some extent. While a commensurate antiferromagnetic ordered state appears for T-N2 < T < T-N1, a partially incommensurate antiferromagnetic ordered state is suggested for T < T-N2.