Quantum emitter-based schemes for the generation of photonic graph states offer a promising, resource-efficient methodology for realizing distributed quantum computation and communication protocols on near-term hardware. We present a heralded scheme for making photonic graph states that is compatible with the typically poor photon collection from state-of-the-art coherent quantum emitters. We demonstrate that the construction time for large graph states can be polynomial in the photon collection efficiency, as compared to the exponential scaling of current emitter-based schemes, which assume deterministic photon collection. The additional overhead here consists of an extra spin qubit plus one additional spin-spin entangling gate per photon added to the graph. While the proposed scheme requires both non-demolition measurement and efficient storage of photons in order to generate graph states for arbitrary applications, we show that many useful tasks, including measurement-based quantum computation, can be implemented without these requirements. As a use case of our scheme, we construct a protocol for secure two-party computation that can be implemented efficiently on current hardware. Estimates of the fidelity to produce graph states used in the computation are given assuming current and near-term fidelities for highly coherent quantum emitters.

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A new heralded scheme for generating photonic graph states addresses the challenge of poor photon collection efficiency in quantum emitters. The approach achieves polynomial scaling in construction time versus photon collection efficiency, compared to exponential scaling in existing methods. The scheme requires an extra spin qubit and one additional entangling gate per photon, but enables practical applications like measurement-based quantum computation and secure two-party computation on current hardware without requiring non-demolition measurement or efficient photon storage for many use cases.

Heralded photonic graph states with inefficient quantum emitters