Hong – Ou – Mandel interference and quantum entanglement of photons on a coupled waveguide beamsplitter

It is generally accepted in quantum optics that the reflection and transmission coefficients in a beam splitter are constant values. If we choose a beam splitter in the form of coupled waveguides, then it can be shown that such a beam splitter is frequency-dependent (depends on the frequency characteristics of input photons) and it is not always correct to consider these coefficients constant.

It will be shown that the well-known Hong – Ou – Mandel effect can be significantly changed in coupled waveguide beam splitters. It will also be shown that the quantum entanglement of photons and their statistics on such beam splitters can differ significantly from a beam splitter with constant reflection and transmission coefficients