In this work, we propose and study a double Kondo lattice model which hosts robust superconductivity. The system consists of two identical Kondo lattice models in two separate layers, with Kondo coupling $J_K$ within each layer, while the localized spin moments are coupled together via an interlayer on-site antiferromagnetic spin coupling $J_{\perp }$. We consider the strong $J_{\perp }$ limit, wherein the local moments tend to form rung singlets and are thus gapped. However, the Kondo coupling $J_K$ transmits the interlayer entanglement between the local moments to the itinerant electrons. Consequently, the itinerant electrons experience a strong interlayer antiferromangetic spin coupling and form strong interlayer pairing, which is confirmed through numerical simulation in one dimensional system. Experimentally, the $J_K\to -\infty$ limits of the model describes the recently found bilayer nickelate ${\mathrm{La}}_3{\mathrm{Ni}}_2{\mathrm{O}}_7$, while the $J_K>0$ side can be realized in tetralayer optical lattice of cold atoms. Two extreme limits, $J_K\to -\infty$ and $J_K\to +\infty$ limit are shown to be simplified to a bilayer type II t-J model and a bilayer one-orbital t-J model, respectively. Thus, our double Kondo lattice model offers a unified framework for nickelate superconductor and tetralayer optical lattice quantum simulator upon changing the sign of $J_K$. We highlight both the qualitative similarity and the quantitative difference in the two sides of $J_K$. Finally, we discuss the possibility of a symmetric Kondo breakdown transition in the model with a symmetric pseudogap metal corresponding to the usual heavy Fermi liquid.

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• Superconductivity
• Nickelates
• Strongly correlated systems
• Kondo lattice model
• t-J model