# Generation of pseudo-sunlight via quantum entangled photons and the interaction with molecules

## TL;DR

This paper proposes a method to emulate sunlight's photon statistics using quantum entangled photons generated via parametric down-conversion, enabling the study of molecular dynamics under sunlight-like conditions.

## Contribution

It introduces a theoretical framework to replicate sunlight's properties with entangled photons, allowing real-time investigation of photo-induced molecular processes.

## Key findings

- Photon number statistics of sunlight can be emulated
- Spectral distribution of sunlight can be reconstructed
- Entanglement time controls photon arrival resolution

## Abstract

Light incident upon molecules trigger fundamental processes in diverse systems present in nature. However, under natural conditions, such as sunlight illumination, it is impossible to assign known times for photon arrival owing to continuous pumping, and therefore, the photo-induced processes cannot be easily investigated. In this work, we theoretically demonstrate that characteristics of sunlight photons such as photon number statistics and spectral distribution can be emulated through quantum entangled photon pair generated with the parametric down-conversion (PDC). We show that the average photon number of the sunlight in a specific frequency spectrum, e.g., the visible light, can be reconstructed by adjusting the PDC crystal length and pump frequency, and thereby molecular dynamics induced by the pseudo-sunlight can be investigated. The entanglement time, which is the hallmark of quantum entangled photons, can serve as a control knob to resolve the photon arrival times, enabling investigations on real-time dynamics triggered by the pseudo-sunlight photons.