Two-exponential decay of Acridine Orange

TL;DR

This study experimentally analyzes the fluorescence decay of Acridine Orange, confirming a two-exponential decay pattern with specific lifetimes and no late-time power-law behavior, thus validating the experimental approach.

Contribution

The paper provides the first precise experimental confirmation of a two-exponential decay model for Acridine Orange fluorescence at late times.

Findings

Decay described by two exponential functions with specific lifetimes.

No evidence of late-time power-law decay behavior.

Experimental setup reliably measures fluorescence lifetimes.

Abstract

In this work, we experimentally study the fluorescence decay of Acridine Orange at late times, in order to test whether a late-time power-law behaviour emerges, a feature expected to be very small but consistent with quantum mechanical and quantum field theoretical predictions. Using two distinct photon detectors, we find that the data are well described by a sum of two exponential functions with lifetimes $\tau_1 = 1.7331 \pm 0.001$ ns and $\tau_2 = 5.948 \pm 0.012$ ns, in agreement with values reported in the literature. While no deviation from the exponential decay law is observed, this study serves as a reliable test for the experimental setup and enables a precise determination of the sample lifetimes.