We present a microscopic model [1] for superconductivity in bilayer nickelates. The model reveals the physical mechanism by which in-plane compressive strain stabilizes the superconducting state against charge- and magnetic order. Cooper pairing is mediated by weakly dispersive singlet-triplet excitations (“triplons”) of interlayer spin dimers. The calculated hierarchy of superconducting gaps on different bands and their angular dependence [2] are in good agreement with experimental data. The global phase diagram of the model is also discussed.

[1] G. Khaliullin and J. Chaloupka, Phys. Rev. B 113, L041115 (2026).

[2] H. Liu and G. Khaliullin, arXiv:2602.23989.