Characteristic energy scales for field-tuned quantum criticality of CeCoIn$_5$

The Phase diagram of field-tuned quantum criticality in CeCoIn$_5$ was characterized by comparative electrical and thermal conductivity measurements. Main two findings for $J \parallel a$ are: (1) finite characteristic temperature of spin fluctuations, $T_{SF}$, terminates linear in $T$ resistivity observed at high temperatures; (2) the Wiedemann-Franz law is obeyed in $T \to 0$ limit, so that the integrity of quasiparticles is preserved, even though the standard $T^2$ Fermi-liquid temperature dependence of resistivity fails. A comparison with inter-plane transport revealed pronounced anisotropy of the phenomenology. 1. J. Paglione, et al. PRL 97, 106606 (2006).