An information entropy interpretation of photon absorption by dielectric media*

We measured photon absorption in dielectric media and proposed the photon-version Beer–Lambert’s law to quantify the absorption. We used a Hong–Ou–Mandel interferometer and 810 nm twin-photons. We found that the depth ratio of the null point in the interference patterns of the interferometer agreed with the classical transmittance of the samples. We established a statistical model of the photon absorption process and proposed an information entropy interpretation to understand the meaning of the Beer–Lambert law. Comparisons of the results of the photon absorption experiments with classical experiments demonstrate the validity of our model and interpretation.