Quantum Critical Behavior and Superconductivity in new multi-site Cerium Heavy Fermion Compound Ce3PtIn11
Abstrakt
We discuss the results of thermodynamic and transport measurements at ambient and under hydrostatic pressure of the recently discovered heavy fermion superconductor Ce3PtIn11. At p = 0 superconductivity emerges in the complex antiferromagnetic state below T-c = 0.32 K.
Both phenomena coexist in a wide range of the p T phase diagram. The critical pressure where T-N -> 0 and T-c is maximum equals p(c) = 1.3 GPa.
Here, the resistivity follows rho(T) proportional to T-n with n = 0.90 +/- 0.05 suggesting a local moment-type of quantum critical point. The presence of a maximum structure in the susceptibility and the unusual pressure dependence of T-c hint to an understanding of properties of Ce3PtIn11 in the view of distinct different Kondo screened sublattices.
Therefore, we analyze the magnetic entropy S-mag within the spin-1/2 Kondo model while accounting for the fact that Ce3PtIn11 unit cell possesses two inequivalent Ce-sites, Ce1 and Ce2. We employ an extreme case scenario of non-interacting sublattices where the Ce1-sublattice is paramagnetic and only Ce2-sublattice orders magnetically and discussed its consequences.