Near-Video Frame Rate Quantum Sensing Using Hong-Ou-Mandel Interferometry

Hong-Ou-Mandel (HOM) interference, bunching of two indistinguishable photons on a balanced beam-splitter, has emerged as a promising tool for quantum sensing. There is a need for wide spectral-bandwidth photon pairs (for high-resolution sensing) with high brightness (for fast sensing). Here, the generation of photon-pairs with flexible spectral-bandwidth even using single-frequency, continuous-wave diode laser enabling high-precision, real-time sensing is showed. Using 1-mm-long periodically-poled KTP crystal, degenerate, photon-pairs with spectral-bandwidth of 163.42 & PLUSMN;1.68 nm are produced resulting in a HOM-dip width of 4.01 & PLUSMN;0.04 & mu;$\umu$m to measure a displacement of 60 nm, and sufficiently high brightness to enable the measurement of vibrations with amplitude of 205 & PLUSMN; 0.75 nm and frequency of 8 Hz. Fisher-information (FI) and maximum likelihood estimation enables optical delay measurements as small as 4.97 nm with precision (Cramer-Rao bound) and accuracy of 0.89 and 0.54 nm, respectively, therefore showing HOM sensing capability for real-time, precision-augmented, in-field quantum sensing applications. Hong-Ou-Mandel interference, has emerged as a promising tool for quantum sensing. There is a need for wide spectral-bandwidth photon pairs (for high-resolution sensing) with high brightness (for fast sensing). Here, the generation of photon-pairs with flexible spectral-bandwidth even using single-frequency, continuous-wave diode laser enabling high-precision, real-time quantum sensing is shown.image

Automated summary

This study demonstrates the generation of photon pairs with flexible spectral bandwidth using a single-frequency continuous-wave diode laser, enabling high-precision, real-time quantum sensing. The photon pairs produced using a specific crystal exhibit sufficient brightness to measure vibrations and optical delay, showcasing their importance in in-field quantum sensing applications.