From first principles to mesoscale quantum dynamics: investigating polaron transport in transition metal oxides for better design principles

Transition metal oxides (TMOs) have garnered significant attention due to their applications in photocatalysis and solar fuel conversion. Polarons—electronic excitations coupled to local lattice distortions—serve as the primary energy carriers in many TMOs. To design better materials, it is crucial to understand the microscopic factors governing polaron migration. Here, we present a unified theoretical framework that connects electronic structure and quantum dynamics across multiple length and time scales. We first characterize the electronic and phononic degrees of freedom of TMOs using first-principles calculations, and then integrate those into numerically exact quantum dynamics simulations of a dispersive Holstein lattice—the prototypical fruitfly to understand localized charge-phonon coupling in condensed matter physics. Leveraging our recent advances in generalized quantum master equations that exploit temporal and spatial memory, we access experimentally relevant time and length scales, enabling direct comparison with measured transport properties. Our framework captures both polaron formation times and electron and hole polaron mobilities, providing a powerful tool to disentangle the effects of microscopic interactions on transport. We demonstrate this approach for a series of TMOs, showing how our method enables quantitative insights and design principles for tailoring polaron dynamics in sustainable energy materials.