Here is something you might be interested in! Together with colleagues in Canada and Italy, we just published a Key Issues Review on two-photon interferences, i.e. the Hong-Ou-Mandel effect! It covers a broad range from the underlying physics, to its applications in quantum information science as well as extension to more particles and analogs in other systems. Enjoy reading it (link).
Thank you Fred, Ebrahim and all co-authors for this great work!