Material properties and functions are governed by dynamics, as well as structures. The dynamics, in other words, the structural evolution and fluctuations at the room temperature stem from the thermal population of low frequency vibrational modes. Based on the knowledge obtained from the 2D EPC spectroscopy, we are interested in revealing the role of a particular low frequency mode by selectively driving the target mode. With this resonant control, we selectively manipulate a specific mode that is revealed to be coupled to particular electronic transitions by strong field THz pulses. We currently study lattice driven optical property changes and electronic/structural phase transitions.
Besides, strong field THz light source enables us to control the electronic structure in a non-resonant manner by driving the system to an extreme state of matter. This approach enables us to modulate optical property of a material with high modulation depth, ultrafast response time, and all-optical/contact free configuration.