Evolution of the Hall effect in CeCoIn$_5$; non-Fermi to Fermi liquid crossover

Heavy fermion superconductor CeCoIn$_5$ ($T_{\rm c}$=2.3K) is located in the vicinity of the antiferromagnetic quantum critical point (QCP). At ambient pressure, the transport properties show non-Fermi liquid behavior, for example, the resistivity $\rho \propto T$. With applying pressure, non-Fermi liquid behavior is suppressed and Fermi liquid behavior recovers. To investigate the electronic transport properties in non-Fermi and Fermi liquid regions, we measured the pressure dependence of the normal-state Hall effect of CeCoIn$_5$ up to 2.51 GPa. At ambient pressure, the Hall coefficient varies as $R_{\rm H} \propto T^{-1}$. With increasing pressure, $R_{\rm H}$ approaches $T$-independent value which is expected for conventional Fermi liquid metals. These results indicate that $T^{-1}$- dependence of $R_{\rm H}$ is a new hallmark of electronic transport properties in the presence of strong antiferromagnetic spin fluctuation near a QCP.