Photon number resolution without optical mode multiplication

Abstract Common methods to achieve photon number resolution rely on fast on-off single-photon detectors in conjunction with temporal or spatial mode multiplexing. Yet, these suffer from an inherent trade-off between the efficiency of discrimination and detection rate. Here, we introduce a method resolving that overcomes limitations by replacing multiplexing coherent absorption single optical distributed detector array. Distributed ensures complete uniform light among constituent detectors, enabling efficient resolution. As proof-of-concept, consider case array superconducting nanowire realistic parameters show deterministic arbitrarily high can be achieved increasing Photon without multiplication provides simple yet effective discriminate arbitrary photons large arrays smaller multiplexed detectors.