Density matrix renormalization group study of quantum-geometry-facilitated pair density wave order

Abstract

Understanding the formation of novel pair density waves (PDWs) in strongly correlated electronic systems remains challenging. Recent mean-field studies suggest that PDW phases may arise in strong-coupling multiband superconductors by virtue of the quantum geometric properties of paired electrons. However, scrutiny through sophisticated many-body calculations has been lacking. Employing large-scale density matrix renormalization group calculations, we obtain in the strong-coupling regime the phase diagram as a function of doping concentration and a tuning interaction parameter for a simple two-orbital model that incorporates quantum geometric effects. The phase diagram reveals a robust PDW phase spanning a broad range of parameters, characterized by a Luttinger parameter $K_{sc} \sim 0.3$ and the absence of coexisting competing spin or charge density wave orders. The observed pairing field configuration aligns with the phenomenological understanding that quantum geometry can promote PDW formation. Our study provides the most compelling numerical evidence to date for quantum-geometry-facilitated intrinsic PDW order in strongly correlated systems, paving the way for further exploration of novel PDW orders and quantum geometric effects in such systems.