Superconductivity is usually assumed to arise from an attractive interaction. In this work we show that strong pairing is possible solely from kinetic energy even without a net attraction. We demonstrate a high-temperature kinetic superconductor in a simple lattice model with nearest-neighbor hopping ($t$) projected onto a constrained Hilbert space, analogous to the $t\text{−}J$ model with $J=0$, where kinetic magnetism has been previously studied. Using density matrix renormalization group (DMRG) on cylinders up to width $L_y=8$, we find a superconducting ground state exhibiting a key difference from high-$T_c$ cuprates: both the pairing gap and phase stiffness increase with doping ($x$). We find pairing gaps, determined from spin and single-electron charge gaps, exceeding $1.5t$. This model can be realized within the double Kondo lattice model, relevant to bilayer nickelates, in the limit of strong interlayer spin coupling ($J_{\perp }/t\to +\infty$) and a balancing interlayer repulsion ($V$). Importantly, the double Kondo model does not fundamentally restrict $J_{\perp }/t$, suggesting the potential for high critical temperatures ($T_c$) approaching $0.5t$. While this idealized limit predicts large pairing gaps, we show a smooth connection to the more realistic regime with $J_{\perp }\sim t$, albeit with a reduced pairing gap of approximately $0.1t$. Assuming $t\sim {10}^3\mathrm{K}$ in typical solid-state systems, our model suggests the exciting possibility of achieving $T_c$ of hundreds of Kelvin. We propose searching for bilayer materials with reduced out-of-plane lattice constants to better approximate the conditions of our ideal model.

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• Density matrix renormalization group
• High-temperature superconductors
• Lattice models in condensed matter