Two-Exponential Decay of Acridine Orange

Abstract

In this work, we experimentally study the fluorescence decay of acridine orange at late times to test whether 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 the sum of two exponential functions with lifetimes τ₁ = 1.7331 ± 0.001 ns and  τ₂ = 5.948 ± 0.012 ns, in agreement with values reported in the literature. Although no deviation from the exponential decay law is observed, this study serves as a reliable test of the experimental setup and enables a precise determination of the sample lifetimes.