# Multi-color quantum control for suppressing ground state coherences in two-dimensional electronic spectroscopy

## TL;DR

This paper introduces a multi-color quantum control method to suppress ground state coherences in two-dimensional electronic spectroscopy, enabling clearer observation of excited state dynamics in complex systems.

## Contribution

The work presents a novel coherent control scheme that isolates excited state coherences by suppressing ground state signals, validated through numerical simulations on a model dimeric system.

## Key findings

- The control scheme effectively suppresses ground state coherences.
- Enhanced clarity in excited state spectral features.
- Potential to improve analysis of complex biological systems.

## Abstract

The measured multi-dimensional spectral response of different light harvesting complexes exhibits oscillatory features which suggest an underlying coherent energy transfer. However, making this inference rigorous is challenging due to the difficulty of isolating excited state coherences in highly congested spectra. In this work, we provide a coherent control scheme that suppresses ground state coherences, thus making rephasing spectra dominated by excited state coherences. We provide a benchmark for the scheme using a model dimeric system and numerically exact methods to analyze the spectral response. We argue that combining temporal and spectral control methods can facilitate a second generation of experiments that are tailored to extract desired information and thus significantly advance our understanding of complex open many-body structure and dynamics.