Quantum Interference dynamics in chip-scale Photonic Boson Sampling Circuit

Abstract

Boson sampling is a leading platform for exploring many-body quantum interference in linear optical systems. However, identifying circuit-level operating regimes where quantum signatures remain robust under realistic conditions remains challenging. In this work, multimode photonic boson sampling is investigated using a programmable six mode integrated photonic circuit composed of cascaded beam splitters and tunable phase shifters. Each beam splitter is realized through directional couplers combined with local phase control, enabling arbitrary unitary transformations within the linear optical circuit. The circuit is modeled using a tight-binding Hamiltonian allowing controlled manipulation of optical phases and inter-mode coupling that directly governs multiphoton interference pathways. This set up is utilised to do the analysis of Heavy Output Generation (HOG), Total Variation Distance (TVD) and Linear Cross-Entropy Benchmarking (XEB), together with configuration-resolved probability differences, for up to five photons. Distinct dynamic regimes associated with coherent evolution, optimal interference and phase dispersion induced mixing is identified. The results further reveal a photon number dependent complexity–fragility trade-off and demonstrate the robustness of TVD to symmetric photon loss under post-selection. Overall, this work establishes a circuit-relevant validation framework linking programmable interferometer parameters, phase control and quantum interference metrics, providing guidance for scalable photonic boson-sampling implementations in the NISQ regime. © 1965-2012 IEEE.