Quantum late-time decay and channel dependence
Phys. Rev. A 114, 012218 – Published 31 July, 2026
DOI: https://doi.org/10.1103/6r7p-mjxb
Abstract
Quantum mechanics predicts deviations from exponential decay at short and long times, yet experimental evidence is limited. We report a power-law tail after lifetimes in two fluorescent compounds (erythrosine B and eosine Y), confirmed by two detectors probing distinct bands but yielding different power coefficients. The data match a divergent but normalizable spectral density, and theory predicts oscillations as a future test. A general result is that, in multichannel quantum mechanics (and quantum field theory) decay, the lifetime is universal, but the late-time deviations are channel dependent (or band dependent), a feature consistent with our data.
