Coherent exciton dynamics in supramolecular light-harvesting nanotubes revealed by ultrafast quantum process tomography.

摘要: Long-lived exciton coherences have been recently observed in photosynthetic complexes via ultrafast spectroscopy, opening exciting possibilities for the study and design of coherent transport. Yet, ambiguity spectroscopic signals has led to arguments against interpreting them terms dynamics, demanding more stringent tests. We propose a novel strategy, quantum process tomography (QPT), spectroscopy apply it reconstruct evolving state excitons double-walled supramolecular light-harvesting nanotubes at room temperature from eight narrowband transient grating experiments. Our analysis reveals absence nonsecular processes, unidirectional energy transfer outer inner wall states, coherence between those states lasting about 150 fs, indicating weak electronic coupling walls. work constitutes first experimental QPT “warm” complex system provides an elegant scheme maximize infor...