Comment on 'multiple stimulated emission fluorescence photoacoustic sensing and spectroscopy' (Appl. Phys. Lett. 109, 013701 (2016))

摘要

Li et al. propose a method and analytic theory for the generation of photoacoustic (PA) signals in fluorophores using pump-probe excitation in which stimulated emission (SE) results in multiple excitation-de-excitation cycles, and therefore a change in the PA signal amplitude.1 In the introduction it is suggested that this method represents a major improvement over a methodology previously reported in Mark et al.,2 which is described as limited in scope and validity, i.e., only applicable to single stimulated emission (SE) transitions with correspondingly weak contributions to the thermalized energy and the amplitude of the PA difference signal. We disagree with this statement and would like to discuss the strengths and limitations of the two models.