Engineering Chiral Topological Superconductivity in Twisted Ising Superconductors

Van der Waals materials like NbSe₂ or TaS₂ have demonstrated Ising superconductivity down to atomically thin layers. Due to the spin-orbit coupling, these superconductors have the in-plane upper critical magnetic field far beyond the Pauli limit. We theoretically demonstrate that, twisted bilayer Ising superconductors separated by a ferromagnetic buffer layer can naturally host chiral topological superconductivity with Chern numbers, which can be realized in heterostructures like NbSe₂/CrCl₃/NbSe₂. Under appropriate experimental conditions the topological superconducting gap can reach >0.1 meV, leading to readily observable signatures such as the quantized thermal Hall transport at low temperatures.