Interaction-driven higher-order topology in superconducting altermagnets

Determine whether the proposed higher-order corner modes in superconducting altermagnets can be obtained from the class of interacting extended Lieb lattice Hubbard models studied here.

Background

The paper establishes that altermagnetic order, Ising-type spin-orbit coupling, and second-order topological corner modes can emerge from interactions in an extended Lieb lattice Hubbard model. It then identifies superconducting altermagnets as a related setting in which higher-order corner modes have been proposed, but does not determine whether the interacting model class analyzed in the paper can realize those superconducting topological features. The problem is therefore to extend the interaction-driven framework to superconducting altermagnetic phases and assess whether their proposed corner modes occur.