Freiburg 2019 – wissenschaftliches Programm
FM 37.3: Talk
Dienstag, 24. September 2019, 14:30–14:45, 3042
Design principles for long-range energy transfer at room temperature — •Andrea Mattioni, Felipe Caycedo-Soler, Susana Huelga, and Martin Plenio — Ulm University, Ulm, Germany
Typical room temperature conditions hinder ballistic long-range transfer of excitations, and are hence considered to prevent quantum phenomena to serve as tools for the design of efficient and controllable energy transfer over significant time and length scales. However, it is well-known that relevant dynamical properties of many-body systems depend on the quantum properties of minimal repeating units and, as we show here, excitonic energy transfer is no exception. With the support of an exactly solvable model, we are able to show how exciton delocalization and the ensuing formation of dark states within unit cells can be harnessed to support classical propagation over macroscopic distances. We specifically discuss the role of such factors in nano-fabricated arrays of bacterial photosynthetic complexes via extensive simulations. This allows us to resolve the until now unexplained experimental observation of exciton diffusion lengths in such arrays in terms of an interplay between intra-unit cell thermalization and delocalization, which cooperate to create and use robust dark states at room temperature. Based on these factors, we provide quantum design guidelines at the molecular scale to optimize both energy transfer speed and diffusion range over macroscopic distances in artificial light-harvesting architectures.