Professor Marien Simeni at ECE Spring 2024 Colloquium

Ultrafast light-matter interactions for probing properties of gases and plasmas

The fourth state of matter, commonly referred to as “plasma,” plays a significant role in our everyday lives on Earth. Examples abound, ranging from its use as light sources to virus inactivation and high-volume manufacturing. Particularly noteworthy is the semiconductor industry, which greatly benefits from advancements in the field of plasma. In light of the quantum computing era and the semiconductor industry’s shift from microelectronics to nanoelectronics, the optimization of plasma processes has become more crucial than ever. In the initial segment of this presentation, I will delve into the ongoing research endeavors of my group, focusing on comprehending fundamental plasma properties. The ultimate aim is to enhance the efficiency of extreme ultraviolet lithography, the current leading technology for patterning surfaces at the nanometer scale. Our emphasis will be on electron properties and their correlation with radiation transport. Moving on to the second part of this discussion, I will showcase the foundational work undertaken by my group to develop innovative laser-based techniques for probing plasma properties at both the picosecond temporal scale and micrometer spatial scale. A particular highlight will be the exploration of three-wave mixing in the gas phase —a process once considered forbidden but now holding great promise for high-sensitivity number density measurements of both atomic and molecular species.