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arXiv · 1807.04846

Signatures of Exciton Delocalization and Exciton-Exciton Annihilation in Fluorescence-Detected Two-Dimensional Coherent Spectroscopy

Pavel Malý·Tomáš Mančal
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Abstract

We present calculations of the fluorescence-detected coherent two-dimensional (F-2DES) spectra of a molecular heterodimer. We compare how the F-2DES technique differs from the standard coherently detected two-dimensional (2DES) spectroscopy in measuring exciton delocalization. We analyze which processes contribute to cross-peaks in the zero-waiting-time spectra obtained by the two methods. Based strictly on time-dependent perturbation theory, we study how in both methods varying degree of cancellation between perturbative contributions gives rise to cross-peaks, and identify exciton annihilation and exciton relaxation contributions to the cross-peak in the zero-waiting-time F-2DES. We propose that time-gated fluorescence detection can be used to isolate the annihilation contribution to F-2DES both to retrieve information equivalent to 2DES spectroscopy and to study annihilation contribution itself.

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Pavel Malý, Tomáš Mančal. 2018-07-12. Signatures of Exciton Delocalization and Exciton-Exciton Annihilation in Fluorescence-Detected Two-Dimensional Coherent Spectroscopy. https://arxiv.org/abs/1807.04846

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