2025/10/26 by Yaish, Netanel P., Gokhale, Samata, Peer, Avi
#FOS: Physical sciences #Optics (physics.optics) #Quantum Physics (quant-ph)
paper · doi:10.48550/arxiv.2510.22677
We demonstrate both the generation and detection of an ultra-high flux of polarization Bell states using broadband hyper-entangled bi-photons that are quantum-correlated in both polarization and time-energy. Bell states of polarization embody the most basic form of two-state entanglement, and are a key component of quantum protocols of communication and sensing. High-speed generation, processing and detection of polarization Bell-states is therefore critical for quantum technology. However, all current protocols that employ polarization entangled photons are inherently slow, primarily due to the photo-detectors (Photomultiplier tubes, avalanche photo-diodes, etc.) that can handle only 106-7 photons/s, whereas sources may easily produce 1010-13 photons/s or more (if properly designed). We fully alleviate this detection bottleneck by resorting to physical detection of the bi-photons with nonlinear interferometry. We harness a generalized, dual polarization SU1,1 interferometer to generate, manipulate and measure all the triplet Bell-states at a flux of ∼ 5×1011 photons/s, enhancing the speed of quantum processing by >5 orders of magnitude compared to standard methods.