Observing optical coherence across Fock layers with weak-field homodyne detectors

Abstract

Quantum properties of optical modes are typically assessed by observing their photon statistics or the distribution of their quadratures. Both particle- and wave-like behaviours deliver important information, and each may be used as a resource in quantum-enhanced technologies. Weak-field homodyne detection provides a scheme which combines the wave- and particle-like descriptions. Here we show that it is possible to observe a wave-like property such as the optical coherence across Fock basis states in the detection statistics derived from discrete photon counting. We experimentally demonstrate these correlations using two weak-field homodyne detectors on each mode of two classes of two-mode entangled states. Furthermore, we theoretically describe the response of weak-field homodyne detection on a two-mode squeezed state in the context of generalised Bell inequalities. Our work demonstrates the potential of this technique as a tool for hybrid continuous/discrete-variable protocols on a phenomenon that explicitly combines both approaches.

19 pages, 12 figures (arXiv version) -- Supplementary Figure 7 modified and minor typos fixed

References in corpus (13)

• Steering, Entanglement, Nonlocality, and the EPR Paradox
• Heralded Generation of Ultrafast Single Photons in Pure Quantum States
• Measuring measurement
• Conditional preparation of single photons using parametric downconversion: A recipe for purity
• Optical continuous-variable qubit
• Multi-photon state engineering by heralded interference between single photons and coherent states
• Mapping coherence in measurement via full quantum tomography of a hybrid optical detector
• Probing the negative Wigner function of a pulsed single photon point by point
• Direct, Loss-Tolerant Characterization of Nonclassical Photon Statistics
• Measuring bipartite quantum correlations of an unknown state
• Homodyne estimation of Gaussian quantum discord
• Witnessing trustworthy single-photon entanglement with local homodyne measurements
• Arbitrarily High Super-Resolving Phase Measurements at Telecommunication Wavelengths

Cited by in corpus (14)

• Uncovering Quantum Correlations with Time-Multiplexed Click Detection
• Direct calibration of click-counting detectors
• Balanced homodyne detection with on-off detector systems: Observable nonclassicality criteria
• Beating the standard quantum limit for binary phase-shift-keying discrimination with a realistic hybrid feed-forward receiver
• Low-noise Balanced Homodyne Detection with Superconducting Nanowire Single-Photon Detectors
• Assessing a binary quantum channel exploiting a Silicon photomultiplier based hybrid receiver
• A robust hybrid receiver for binary phase-shift keying discrimination in the presence of phase noise
• Displaced photon-number entanglement tests
• On the application of a Silicon photomultiplier-based receiver for binary phase-shift-keying protocols
• Employing weak-field homodyne detection for quantum communications
• Quantum communications in continuous variable systems
• A Tractable Protocol for Detection-Loophole-Free Bell Tests over Long Distances
• Non-Gaussian entanglement criteria for atomic homodyne detection
• Open dynamics of entanglement in mesoscopic bosonic systems