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arXiv · 1502.06410

Linear, third- and fifth-order nonlinear spectroscopy of a charge transfer system coupled to an underdamped vibration

Arend G. Dijkstra·Yoshitaka Tanimura
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Abstract

We study hole, electron and exciton transport in a charge transfer system in the presence of underdamped vibrational motion. We analyze the signature of these processes in the linear and third-, and fifth-order nonlinear electronic spectra. Calculations are performed with a numerically exact hierarchical equations of motion method for an underdamped Brownian oscillator spectral density. We find that combining electron, hole and exciton transfer can lead to non-trivial spectra with more structure than with excitonic coupling alone. Traces taken during the waiting time of a two-dimensional spectrum are dominated by vibrational motion and do not reflect the electron, hole, and exciton dynamics directly. We find that the fifth-order nonlinear response is particularly sensitive to the charge transfer process. While third-order 2D spectroscopy detects the correlation between two coherences, fifth-order 2D spectroscopy (2D population spectroscopy) is here designed to detect correlations between the excited states during two different time periods.

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Arend G. Dijkstra, Yoshitaka Tanimura. 2015-02-23. Linear, third- and fifth-order nonlinear spectroscopy of a charge transfer system coupled to an underdamped vibration. https://doi.org/10.1063/1.4917025

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