In-115 NQR study with evidence for two magnetic quantum critical points in dual Ce site superconductor Ce3PtIn11
Abstrakt
In-115 nuclear quadrupole resonance (NQR) measurements have been carried out on Ce3PtIn11, a heavy fermion compound harboring two inequivalent Ce sites. This system exhibits magnetic transitions at T-1n = 2.2 K and T-N = 2 K, prior to entering a superconducting state below T-c = 0.32 K.
Previous measurements imply that magnetism and superconductivity are spatially separated and only the Ce(2) sublattice orders magnetically, with a quantum critical point at pressure p(c) = 1.3 GPa, while the Ce(1) sublattice is paramagnetic. However, the present nuclear relaxation rate behavior of 1/T-1 proportional to root T reveals the presence of critical spin fluctuations indicative of close proximity to another quantum critical point, presumably at a small negative pressure, which is associated solely with the Ce(1) sublattice.
The ordered wave vector is found to be most likely (1/2, 1/2, h).