Two-photon spectral modulation via temporal manipulation: Quantum optical synthesis of spectral modes from temporal square waves

Precise manipulation of the time–frequency modes entangled photons is crucial for future quantum science and technologies. Recently, frequency-domain-quantum-optical-synthesis (FD-QOS) method was demonstrated by creating a superposition different joint temporal amplitudes: those distributions can be controlled manipulating spectral amplitude in 2D frequency space via Fourier optical relation. This FD-QOS provides an efficient, flexible, easy-to-control way to precisely modulate photon ultrafast region. However, only not sufficient various applications information, since modulations are also needed on many occasions. Here, we present proof-of-concept experiment two-photon modulation biphoton wave packet. protocol, called time-domain-quantum-optical-synthesis (TD-QOS), achieved adjusting relative phases between two distributions. In addition, characterized measuring intensities Hong–Ou–Mandel interferences. The combination TD-QOS enables complete control over states. Our work would further develop technologies that rely photons.