Dynamics of Collective Phase in Molecular Vibrational Polaritons
Abstract
We aim to quantify and control population transfer dynamics between polaritons and dark modes, in order to lay the foundation to prepare a macroscopic collective quantum vibrational state in vibrational polaritons. Chemical reactions involve collisions, electric- or photo-excitations to overcome reaction barriers. Only molecules with very high energy can react, and it has to occur before the energetic molecules dissipate their energy. This process is similar to nonlinear optics. In two-photon absorptions, excited molecules must absorb a second photon before relaxation occurs, which was made possible by the advent of laser. This is due to their high photon density and coherence that ensures multiple photons can interact with the same molecules constructively or destructively. This similarity between nonlinear optics and chemical reactions leads to the possibility of that a macroscopic collection of high-density, coherent excited molecular states can enhance many-body scatterings that lead to rapid accumulation of energy to activate chemical bonds and opening of new mechanisms for chemical reactions. To pursue this possibility, we will conduct the first step by measuring and optimizing dynamics of molecular vibrational polaritons. The specific aims are: (1) quantifying reservoir to polariton relaxation dynamics using ultrafast two-dimensional infrared (2D IR) spectroscopy; (2) optimizing reservoir to polariton relaxation dynamics by creating miniaturized optical cavity modes. 2D IR spectroscopy will be used to measure the reservoir-to-polariton mode relaxation dynamics, which will be done by intermolecular polaritonic vibrational transfer experiments and extracted from kinetic equations. The reservoir-to-polariton relaxation time scale will be optimized by customizing confined cavities on the scale of a few microns. These cavities will be manufactured using photo and e-beam lithographic tools. We anticipate the results will lay the foundation of a new approach to control chemical reactions, with a potential impact to the molecular polariton and chemical catalysis.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 21, 2022
- Source ID
- FA95502110369XX0
Entities
People
- Wei Xiong
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of California, San Diego