Driven Cavity-Controlled Phonons for Quantum Materials Manipulation

Objective

Driven optical and terahertz cavities offer unprecedented opportunities to control lattice vibrations and engineer emergent phases in quantum materials. This project aims to establish a predictive and experimentally verifiable theoretical framework for cavity-controlled phonon dynamics and their coupling to spin, chirality, and topology, and through this, to open a new paradigm for controlling and engineering the properties of quantum materials. By integrating quantum electrodynamical density functional theory (QEDFT), cavity quantum electrodynamics, and effective phonon models, we will develop a quantitative and versatile description of cavity–phonon interactions under both equilibrium and driven conditions. We will demonstrate that the multi-mode phonon beating can enable chirality generation and angular momentum transfer between cavity photons, phonons, and spin excitations even under linearly polarized excitation. Furthermore, we will extend the host group’s recently developed energy-resolved input–output formalism into a momentum-resolved framework, providing direct and experimentally verifiable predictions of energy- and momentum-resolved phonon dynamics. By combining first-principles simulations, tight-binding modeling, and open-system quantum dynamics, this project will deliver a unified, quantitative, and predictive framework to design and control cavity-driven functionalities in next-generation quantum materials.