The role of state preparation in time-bin entangled photon pair generation for quantum communication

Time-bin entangled photons have previously been utilized for advanced quantum communication protocols such as quantum state teleportation or entanglement swapping, thus showing the potential of realizing a quantum internet. For such protocols, intricate feedback systems are essential to preserve quantum information during distribution, and require different forms of state preparation that can incorporate the feedback in quantum state generation. We use different methods of state preparation via arbitrary waveform generators and PLC MachZehnder type interferometers, and entangle the states by SPDC using commercial lithium niobate waveguides to create time-bin entangled photon pairs. Quantum state tomography is conducted on each method to evaluate their effectiveness in generating states suitable for quantum communication protocols.