Layer-dependent Ruppeiner curvature in chiral rhombohedral graphene

We derive the Ruppeiner geometry of rhombohedral graphene multilayers in a chiral low-energy theory. The layer number determines the power-law dispersion, the density of states, and the finite-temperature entropy surface. From the exact carrier density, excitation energy, and entropy, we obtain an analytical expression for the thermodynamic scalar curvature, for general layer number. The curvature is negative, vanishes in the dilute classical limit, and diverges on the charge-neutral branch as temperature is lowered. Its scaling is controlled by the number of layers, showing that chiral band flattening modifies the thermodynamic state space even in the absence of interactions.