Pressure effect of single ion Kondo temperature in Ce$_{.02}$La$_{.98}$RhIn$_{5}$

Near a critical pressure P$_{c} \quad \sim $ 25 kbar, CeRhIn$_{5}$ assumes characteristics of CeCoIn$_{5}$ at atmospheric pressure: they have comparable T$_{C}$, similar dHvA frequencies, and display quantum-critical behaviors. Many properties of CeCoIn$_{5}$ can be interpreted within a two-fluid phenomenology$^{1}$ in which there are interpenetrating fluids, a localized f-electron Kondo gas (energy scale T$_{K})$ and an interacting Kondo liquid (energy scale T*). We have measured transport properties of Ce$_{.02}$La$_{.98}$RhIn$_{5}$ under pressures to 50 kbar to determine T$_{K}$(P), which at P=0 is estimated to be $\sim $ 0.03K from specific heat measurements. T$_{K}$(P) increases rapidly, reaching $\sim $1.35K at 25 kbar, where it becomes comparable to T$_{K}$ ($\sim $1.8K) of CeCoIn$_{5}$ at P=0. A comparison of T$_{K}$(P) with T*(P), determined from the pressure studies of CeRhIn$_{5}$, reveals the same correlation between T$_{K}$ and T* inferred from a two-fluid analysis of CeCoIn$_{5}$, further supporting the similarity of these two compounds and the two-fluid phenomenology. [1] S. Nakatsuji et al., Phys. Rev. Lett. 92, 016401 (2004).