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arXiv · 1506.07837

Two-dimensional coherent photocurrent excitation spectroscopy in a polymer solar cell

Eleonora Vella·Pascal Grégoire·Hao Li·Sachetan M. Tuladhar·Michelle Vezie·Sheridan Few·Jenny Nelson·Eric R. Bittner·Carlos Silva
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Abstract

In high-performance solar cells based on polymeric semiconductors, the mechanism of photocarrier generation on $<100$-fs timescales is yet to be unravelled. In particular the dynamics of early-time electronic coupling between excitons on polymer chains and charge-transfer states need to be investigated in order to develop a detailed picture of ultrafast processes involved in photocurrent production. In this proceeding, we report preliminary measurements using a novel spectroscopy that can measure such correlations: two-dimensional coherent photocurrent excitation spectroscopy. This nonlinear technique measures off-diagonal spectral correlations in a two-dimensional photocurrent excitation spectrum. We interpret these sectroscopic measurements in light of recent theoretical predictions.

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Eleonora Vella, Pascal Grégoire, Hao Li, Sachetan M. Tuladhar, Michelle Vezie, Sheridan Few, Jenny Nelson, Eric R. Bittner, Carlos Silva. 2015-06-25. Two-dimensional coherent photocurrent excitation spectroscopy in a polymer solar cell. https://arxiv.org/abs/1506.07837

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