Dr. Jino George

Associate Professor, Chemical Sciences

Molecular Strong Coupling

Research Focus:

Our group activities are highly interdisciplinary in nature. We study strong interactions between molecular transitions and vacuum field (photon) by placing molecules in an optical resonator or on a plasmonic nanostructure. This offers a unique way to control the energy levels of molecular systems while achieving delocalization through the photonic degrees of freedom offered by cavity or plasmonic modes. Such light-matter strong coupling and the formation of hybrid light-matter states has been extensively studied in quantum optics and condensed matter physics, but its consequences for molecular and material science is just beginning to be explored. Our main focus here is to understand the chemical and physical properties of such newly formed hybrid light-matter states, which are otherwise called as polaritonic states. Two of the major ongoing projects are mentioned below:

1. Chemistry under strong coupling (STRONG^chem)

Strong coupling of light to a vibrational transition should affect chemistry because it offers a simple way to modify a given chemical bond and hence their reactivity landscape. Very recently we experimentally proved that a ground state chemical reaction can be modified by coupling molecular vibrations to vacuum electromagnetic field or zero point energy of a resonant IR micro-fluidic cavity. The focus of the current study is to understand in depth the influence of vibrational strong coupling (VSC) on the chemical reactivity of molecules to determine the underlying principles, to make it as a novel and useful tool for chemists.

2. Light-matter strong coupling for material science (STRONG^matter)

In this project, efforts will be made to study electron/energy transfer processes mediated by extended nature of the polaritonic states of electronically and vibrationally coupled systems. Here, more emphasis will be given for improving the efficiency of transport in molecular materials, both electron and energy transfer rates via the polaritonic states-new field of research coined as ‘polaritronics’. Such hybrid systems will be tested in a home built electro-optical work station for measuring their charge transport and optical properties simultaneously. As mentioned above, polaritonic states can be tuned in terms of their energy levels and understanding the dynamics of energy migration in such hybrid delocalized systems are of potential interest in light harvesting and biological systems.

• Lather, P. Bhatt, A. Thomas, T. W. Ebbesen*, J. George* “Cavity Catalysis by Cooperative Vibrational Strong Coupling of Reactant and Solvent Molecules” Angew. Chem. Int. Ed. 2019, 58, 10635-10638.
• A. Thomas, L. Lethuillier-Karl, K. Nagarajan, R. M. A. Vergauwe, J. George, T. Chervy, A. Shalabney, E. Devaux, C. Genet, J. Moran, T. W. Ebbesen “Tilting a ground-state reactivity landscape by vibrational strong coupling” Science 2019, 363, 615-619.
• H. Hiura, A. Shalabney, J. George “Cavity Catalysis ‒Accelerating Reactions under Vibrational Strong Coupling‒” ChemRxiv 2018; DOI: 10.26434/chemrxiv.7234721.v3.
• A. Thomas*, J. George*, A. Shalabney, M. Dryzhakov, S. J. Varma, J. Moran, T. Chervy, X. Zhong, E. Devaux, C. Genet, J. Hutchison and T.W. Ebbesen “Ground state chemical reactivity under vibrational coupling to the vacuum field” Angew. Chemie Int. Ed. 2016, 55, 11462–11466.
  
• J. George*, T. Chervy*, A. Shalabney, E. Devaux. H. Hiura, C. Genet, T. W. Ebbesen “Multiple Rabi splitting under ultra-strong vibrational coupling” Phys. Rev. Lett. 2016, 117, 153601.
  
• E. Orgiu*, J. George*, J. A. Hutchison*, E. Devaux, J-F. Dayen, B. Doudin, F. Stellacci, C. Genet, P. Samori, T. W. Ebbesen “Conductivity in organic semiconductors mediated by polaritonic states” Nature Materials 2015, 14, 1123–1129.
  
• J. George, S. Wang, T. Chervy, A. Canaguier-Durand, G. Schaeffer, J-M. Lehn, J. A. Hutchison, C. Genet, T. W. Ebbesen “Ultra-strong coupling of molecular materials: Spectroscopy and Dynamics” Faraday Discuss. 2015, 178, 281-294.
  
• J. George, K. G. Thomas “Surface plasmon coupled circular dichroism of Au nanoparticles on peptide nanotubes” J. Am. Chem. Soc. 2010, 132, 2502-2503.