High-Precision Measurement of Time Delay with Frequency-Resolved Hong-Ou-Mandel Interference of Weak Coherent States

Abstract

We demonstrate a scheme for high-precision measurements of time delay based on frequency-resolved Hong-Ou-Mandel (HOM) interference. Our approach is applied to weak coherent states and exploits an array of single-photon avalanche diodes (SPADs). Unlike conventional HOM experiments, our setup enables high-precision measurements producing an uncertainty per coincidence of about $\sim 10$ ps even for photons separated by delays up to $\sim 4$ ps so much greater than their coherence time where ordinary non-resolved HOM fails. This result confirms our newly developed theoretical predictions that consider, differently from previous theoretical results, a finite frequency resolution in the detection. We compare the performance of this scheme against the conventional non-resolved case. Experimental data align well with the predictions of quantum estimation theory, demonstrating a significant reduction in the uncertainty. Due to the physics of the frequency-resolved HOM effect, the gain in precision is particularly high when the estimated time delay is much longer than the coherence time.

12 pages, 6 figures

References in corpus (10)

• Quantum Beat of Two Single Photons
• Spectral Correlation Measurements at the Hong-Ou-Mandel Interference Dip
• Entangling Color-Different Photons via Time-Resolved Measurement and Active Feed-Forward
• Spectrally-resolved Hong-Ou-Mandel interferometry for Quantum-Optical Coherence Tomography
• Tracking the polarisation state of light via Hong-Ou-Mandel interferometry
• Ultimate quantum sensitivity in the estimation of the delay between two interfering photons through frequency-resolving sampling
• Spatial-mode-demultiplexing for enhanced intensity and distance measurement
• Estimation with ultimate quantum precision of the transverse displacement between two photons via two-photon interference sampling measurements
• Superresolution imaging of two incoherent sources via two-photon interference sampling measurements in the transverse momenta
• Momentum-entangled two-photon interference for quantum-limited transverse-displacement estimation

Cited by in corpus (1)

• Momentum-resolved two photon interference of weak coherent states