Controlling quantum entanglement via Houng-Ou-Mandel antibunching

We investigate into experimentally detectable effects determined by the fundamental interplay between the spectral and entanglement properties of biphoton states such as the two-photon interference at beam splitter phenomena known as the Hong-Ou-Mandel (HOM) bunching and antibunching. It is shown that the HOM antibunching effect, which is known to take place only for entangled states, is primarily governed by the parity properties of the biphoton joint spectral amplitude as opposed its permutational symmetry assumed in previous studies. The experimentally accessible classes of modulated biphoton states that satisfy the parity conditions are proposed. By using the Schmidt decomposition, for this class of states, it is revealed a pronounced correlation between the Schmidt number and the two-photon coincidence probability so that the HOM antibunching occurs near extrema of the entanglement degree. It is found that switching between the bunching and antibunching regimes along with entanglement control can be realized using the fine-tuned spectral phase modulation corresponding to path length variations on the sub-nanometer scale or relative time delays on the order of attoseconds.