Duke Physics Colloquium - Moving in a Dynamically Changing Free Energy Landscape: Strain, Heterostructure and Optical Control of the Correlation-Driven Metal-Insulator Transition

A theory [1] of energy landscape in the space of electronic and lattice degrees of freedom is formulated for "Mott" metal-insulator materials is formulated and argued to resolve the long-standing question of the relative importance of electronic and lattice contributions in the Mott metal insulator transition. Moving beyond equilibrium, the theory is used to understand the physics of optically driven metal-insulator transitions. Atomic scale calculations at equilibrium and short times are used to define an energy landscape and the initial evolution of order parameters; longer times are accessed in terms of time dependent Ginzburg-Landau theories. The importance of the time dependence of the landscape is highlighted via modeling of experiments on photo induced superconductivity in the LBCO system [2,3] and the importance of electronic bottlenecks and of electron-lattice effects [4] are explored in the context of a study of the dynamics of the photo induced metal transition in Ca2RuO4
[1] A. Georgescu and A. J. Millis, Communications Physics 5,135 (2022)
[2] K. A. Cremin, J. Zhang, C. C. Homes, G. D. Gu, Z. Sun, M. M. Fogler, A. J. Millis, D. N. Basov, and R. D. Averitt, Proceedings of the National Academy of Sciences 116, 19875 (2019).
[3] Z. Sun and A. J. Millis, Phys. Rev. X 10, 021028 (2020)
[4] A. Verma, D. Golez, A. J. Millis and A. Singer arXiv:2304:02149; Nature Physics, in press