%0 Journal Article %T Waveguide photon-number-resolving detectors for quantum photonic integrated circuits %A D. Sahin %A A. Gaggero %A Z. Zhou %A S. Jahanmirinejad %A F. Mattioli %A R. Leoni %A J. Beetz %A M. Lermer %A M. Kamp %A S. H£¿fling %A A. Fiore %J Physics %D 2013 %I arXiv %R 10.1063/1.4820842 %X Quantum photonic integration circuits are a promising approach to scalable quantum processing with photons. Waveguide single-photon-detectors (WSPDs) based on superconducting nanowires have been recently shown to be compatible with single-photon sources for a monolithic integration. While standard WSPDs offer single-photon sensitivity, more complex superconducting nanowire structures can be configured to have photon-number-resolving capability. In this work, we present waveguide photon-number-resolving detectors (WPNRDs) on GaAs/Al0.75Ga0.25As ridge waveguides based on a series connection of nanowires. The detection of 0-4 photons has been demonstrated with a four-wire WPNRD, having a single electrical read-out. A device quantum efficiency ~24 % is reported at 1310 nm for the TE polarization. %U http://arxiv.org/abs/1308.4606v1