Photon entanglement-enhanced multidimensional spectroscopy of exciton correlations in photosynthetic aggregates

TL;DR

This paper introduces a novel multidimensional spectroscopy method using entangled photon pairs to probe exciton interactions in photosynthetic systems, revealing enhanced sensitivity and resolution at femtosecond timescales.

Contribution

The work demonstrates how entangled photons can improve the detection of exciton correlations and interactions compared to classical pulses in multidimensional spectroscopy.

Findings

Entangled photon pairs outperform classical pulses in manipulating excited-state absorption pathways.

Spectral features correspond to one- and two-exciton resonances, enabling detailed correlation analysis.

Signal strength scales linearly with photon source intensity, facilitating practical experimental setups.

Abstract

Nonlinear spectroscopic techniques using entangled photon pairs can provide an opportunity to exploit non-classical correlations encoded in two-photon wavefunctions to manipulate two-exciton wavefunctions. We propose an entangled photon pair-enhanced multidimensional spectroscopic technique that is sensitive to exciton-exciton interactions and correlations at the femtosecond timescale. Simulations for a dissipative system, namely, the photosynthetic aggregate reveal the superior ability of entangled photon pairs, compared to both transform-limited and frequency-chirped laser pulses, to manipulate excited-state absorption pathways. The corresponding spectral features in the two-dimensional spectrogram are interpreted in terms of one- and two-exciton resonances. The signal scales linearly with the incoming intensity of the photon sources. We show that classifying these resonances using entangled photon source in the perturbative limit allow for probing exciton correlations at the natural energy scale. These insights can be used to explore multi-exciton dynamics in molecular systems using multiphoton entanglement.