Entangled Two-Photon Absorption Spectroscopy with Varying Pump Wavelength

TL;DR

This paper extends entangled two-photon absorption spectroscopy by varying pump wavelengths to better analyze complex energy-level structures, overcoming limitations of traditional methods in multi-state systems.

Contribution

It introduces a novel approach of using repeated measurements at different pump wavelengths to enhance spectral analysis of complex samples.

Findings

Effective for complex multi-state systems

Works with various experimental setups

Improves spectral resolution in entangled photon spectroscopy

Abstract

In virtual-state spectroscopy, information about the energy-level structure of an arbitrary sample is retrieved by Fourier transforming sets of measured two-photon absorption probabilities of entangled photon pairs where the degree of entanglement and the delay time between the photons have been varied. This works well for simple systems but quickly becomes rather difficult when many intermediate states are involved. We propose and discuss an extension of entangled two-photon absorption spectroscopy that solves this problem by means of repeated measurements at different pump wavelengths. Specifically, we demonstrate that our extension works well for a variety of realistic experimental setups.