Photon-driven electron excitations in quantum materials

Abstract

Photon-driven electron excitation is a foundational mechanism underpinning the interaction between light and matter in quantum materials, including van der Waals materials, Dirac and Weyl semi-metals, topological insulators and other emergent phases. These enable next-generation optoelectronic, energy conversion and quantum information technologies. However, translating this mechanistic understanding into an engineering implementation is hindered by excitation efficiency, environmental stability and scalable fabrication. In this Review, we provide a mechanistic perspective on key photon-driven electron-excitation processes based on energy flow pathways, including electron–hole generation in semiconductors, high-mobility electron transport in semi-metals, photoemission from metals and low-dimensional materials, and light-induced thermoelectric effects. We examine engineering strategies to enhance the efficiency of these processes, including interface control, material selection and compatible integration. By bridging fundamental mechanisms with device-level metrics, this Review offers a unified framework and practical roadmap for advancing scalable, multifunctional optoelectronic devices that integrate sensing, data storage and computation. This Review explores photon-driven electron excitations in quantum materials, connecting semiconductor photogeneration, semi-metal transport, photoemission and thermoelectric conversion to device-level trade-offs. It highlights cross-mechanism benchmarking, presenting a roadmap towards complementary metal oxide semiconductor (CMOS)-compatible optoelectronics for integrated sensing, memory, computation and emerging photonic technologies.