Low temperature magnetic phase diagram of the cubic non-Fermi liquid system CeIn $\mathsf{_{3-x}}$Sn$\mathsf{_x}$

Abstract.

In this paper we report a comprehensive study of the magnetic susceptibility ($\chi$), resistivity ($\rho$), and specific heat ($C_{\rm P}$), down to 0.5 K of the cubic CeIn_3-x Sn _x alloy. The ground state of this system evolves from antiferromagnetic (AF) in CeIn₃ ($T_{\rm N} = 10.2$K) to intermediate-valent in CeSn₃, and represents the first example of a Ce-lattice cubic non-Fermi liquid (NFL) system where $T_{\rm N}(x)$ can be traced down to T = 0 over more than a decade of temperature. Our results indicate that the disappearance of the AF state occurs near $x_{\rm c}\approx 0.7$, although already at $x\approx 0.4$ significant modifications of the magnetic ground state are observed. Between these concentrations, clear NFL signatures are observed, such as $\rho(T)\approx\rho_0 + A T^n$ (with n < 1.5) and $C_{\rm P}(T)\propto-T\ln(T)$ dependencies. Within the ordered phase a first order phase transition occurs for 0.25 < x < 0.5. With larger Sn doping, different weak $\rho(T)$ dependencies are observed at low temperatures between x = 1 and x = 3 while $C_{\rm P}/T$ shows only a weak temperature dependence.