LMI Seminar: Molecules in a Quantum-Optical Flask
Dr. Tal Schwartz, Physical Chemistry Department, TAU
Abstract:
When confined to small dimensions, the interaction between light and matter can be enhanced up to the point where it overcomes all the incoherent, dissipative processes. In this "strong coupling" regime the photons and the material start to behave as a single entity, having its own quantum states and energy levels.
In this talk I will present the fundamental physics of strong coupling in hybrid photonic-molecular structures, and how such cavity-QED effects can be employed for controlling material properties and molecular processes. This includes, for example, photochemical reactions [1], the enhancement of transport in organic semiconductors [2-3] and potentially tailoring the mesoscopic properties of organic crystals, by hybridizing intermolecular vibrations with electromagnetic THz fields [4-5]. Finally, I will discuss our recent discovery [6], where we showed that the finite velocity of light and retardation effects must be taken into account in cavity-QED physics.
[1] J. A. Hutchison, T. Schwartz, C. Genet, E. Devaux, and T. W. Ebbesen, "Modifying Chemical Landscapes by Coupling to Vacuum Fields," Angew. Chemie Int. Ed. 51, 1592 (2012).
[2] G. G. Rozenman, K. Akulov, A. Golombek, and T. Schwartz, "Long-Range Transport of Organic Exciton-Polaritons Revealed by Ultrafast Microscopy," ACS Photonics 5, 105 (2018).
[3] M. Balasubrahmaniyam, A. Simkovich, A. Golombek, G. Ankonina, and T. Schwartz, "From enhanced diffusion to ultrafast ballistic motion of hybrid light–matter excitations," Nat. Mater. 22, 338 (2023).
[4] R. Damari, O. Weinberg, D. Krotkov, N. Demina, K. Akulov, A. Golombek, T. Schwartz, and S. Fleischer, "Strong coupling of collective intermolecular vibrations in organic materials at terahertz frequencies," Nat. Commun. 10, 3248 (2019).
[5] M. Kaeek, R. Damari, M. Roth, S. Fleischer, and T. Schwartz, "Strong Coupling in a Self-Coupled Terahertz Photonic Crystal," ACS Photonics 8, 1881 (2021).
[6] M. Balasubrahmaniyam, C. Genet, and T. Schwartz, “Coupling and decoupling of polaritonic states in multimode cavities”. Phys. Rev. B 103, 1 (2021).
