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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Spatial Properties of Entangled Two-Photon Absorption
D Tabakaev1, A Djorović1, L La Volpe1
1Département de Physique Appliquée, Université de Genève, 1211 Genève, Switzerland.
Physical Review Letters
|November 14, 2022
Summary
We studied entangled two-photon absorption in rhodamine 6G using entangled photon pairs. Entangled two-photon absorption shows beam waist dependence similar to classical two-photon absorption, explaining varied literature values.
Area of Science:
- Quantum optics
- Nonlinear spectroscopy
- Photochemistry
Background:
- Entangled two-photon absorption (ETPA) is a quantum phenomenon with potential applications in spectroscopy and imaging.
- Understanding ETPA's dependence on spatial properties is crucial for its practical application.
- Literature values for ETPA cross sections of dyes show significant variation, necessitating further investigation.
Purpose of the Study:
- To experimentally investigate entangled two-photon absorption in rhodamine 6G.
- To analyze the influence of spatial properties, specifically beam waist, on ETPA.
- To compare ETPA's spatial dependence with classical absorption processes.
Main Methods:
- Utilizing a high flux of broadband entangled photon pairs.
- Attenuating entangled pair flux linearly and by reducing laser pump power.
- Performing fluorescence-based Z-scan measurements to probe beam waist dependence.
Main Results:
- Demonstrated a linear dependence of ETPA rate on laser pump power attenuation.
- Showed a quadratic dependence of ETPA rate on linear pair flux loss.
- Observed that ETPA exhibits a beam waist dependence analogous to classical two-photon absorption.
Conclusions:
- The spatial properties, particularly beam waist, significantly influence ETPA.
- The similarity in beam waist dependence between ETPA and classical two-photon absorption provides a unified understanding.
- This finding helps reconcile discrepancies in reported ETPA cross-section values in scientific literature.
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