Time-bin (TB) and energy-time (ET) entanglement are crucial resources for long-distance quantum information processing. Recently, major efforts have been made to produce compact high-quality sources of TB/ET entangled photons based on solid-state integrated technologies. However, these attempts failed to close the so-called "post-selection loophole". Here, we present an integrated photonic general Bell-test chip for genuine (i.e., free of the post-selection loophole) TB and ET entanglement certification. We report a violation of a Bell inequality by more than 10 standard deviations using our device based on the "hug" interferometric scheme. The experiment also demonstrates that the hug scheme, previously exploited for ET entanglement, can also be used for genuine TB entanglement.
@article{arxiv.2302.06522,
title = {Certification of genuine time-bin and energy-time entanglement with integrated photonics},
author = {Francesco B. L. Santagiustina and Costantino Agnesi and Alvaro Alarcón and Adán Cabello and Guilherme B. Xavier and Paolo Villoresi and Giuseppe Vallone},
journal= {arXiv preprint arXiv:2302.06522},
year = {2024}
}