SPDC

Spontaneous Parametric Down-Conversion (SPDC) is a nonlinear optical process widely used to generate entangled photon pairs. In SPDC, a high-energy pump photon passing through a nonlinear crystal is converted into two lower-energy photons, called the signal and idler, while conserving energy and momentum. This process is a cornerstone of experimental quantum optics, providing a reliable source of entanglement for applications in quantum communication, quantum cryptography, and fundamental tests of quantum mechanics. We have extensively used the SPDC process as a key tool in our quantum optics research. Our group employed SPDC sources to generate entangled photon pairs and multipartite entangled states, which were crucial in demonstrating Bell inequality violations, quantum nonlocality, and multi-photon entanglement witnesses. We have also applied SPDC-generated photons in quantum key distribution, secret sharing protocols, and high-dimensional quantum communication experiments, establishing experimental platforms that combine SPDC with optical fibers and integrated photonic systems for practical quantum technologies.

Selected publications