Thursday, March 14, 2024
16:00 - 17:00
Cooperative effects in complex, coupled quantum systems, cannot be understood by sole consideration of the individual constituents, as they arise from the interplay among them. Light-matter platforms provide an optimal playground for the observation and exploitation of quantum cooperative effects [1]. For example, structured subwavelength arrays of quantum emitters trapped in optical lattices, are ideal showcases of such cooperative behavior, as their optical response can be efficiently enhanced by controlling the hopping of surface excitations via the quantum electromagnetic vacuum induced dipole-dipole interactions. Subwavelength arrays can be then employed in hybrid architectures for optical cavities with applications in chiral sensing [2].
While subwavelength separations are not easily achieved in synthetic atomic systems, molecular dimers and molecular aggregates (i.e.~arrays of identical molecules, such as J- and H-aggregates) can feature deeply subwavelength separations, even on the nanometer scale. The downside of such systems is the much more complex structure, which introduces coupling of electronic degrees of freedom with intra- and inter-molecular vibrations. We have introduced a quantum Langevin equations approach to electron-vibron interactions for single molecules subject to either classical or cavity quantum light fields [3]. The extension of this method to many particles allowed us to benchmark the scaling of cooperative effects such as super- and subrradiance to molecular rings or chains and to quantitatively describe couplings among collective electronic states via vibrations, in a process known as Kasha’s rule [4]. Moreover, this toolbox can provide an open system dynamics alternative for quantitatively describing non-adiabatic phenomena in large molecules and reproduce and augment the celebrated energy gap law for radiationless transitions.
UvA-IoP
UvA - Faculty of Science
H0.08
Colloquium
quantum matter
Prof. Dr. Claudiu Genes ( Max-Planck-Institut für die Physik des Lichts)