Regarding the hardware development, several results were achieved in the development of squeezed sources with high squeezing level and efficiency, as well as improvements for single-photon emitters, both in terms of efficiency and interference between remote emitters. Fabrication of integrated circuits for photon manipulations is also currently carried out with all the three main platforms used within the project. Active manipulation components have also been developed, ranging from integrated switches, time-to-spatial demultiplexer modules, and implementation of fast feed-forward systems. Finally, progress has been made in the development of single-photon detectors, including high efficiency systems, waveguide integrated detectors, and high-speed, high-efficiency homodyne detectors. All these components will become part of the assembled machines in the second part of the project. The assembly of the machines have also kicked off in this first part of the EPIQUE project. The architecture for all machines has been defined, and the process to interface the different components in each single machine has started.
Regarding the software part, the consortium has analyzed different photonic quantum computation architectures obtaining several relevant results, in particular on non-universal models for near-term quantum computing and for the generation of GHZ states, as testified by the number of preprint/publications obtain in the period. These results have been also part of the background to define the architecture for the machines. On the verification side, the consortium has developed several benchmarking methods useful to validate the output of quantum computations. These include hardware-specific benchmarking protocols, new measures of non-classicality, and first work to merge all the developed methods in a unique standard for the system validation. Finally, the consortium has also started to identify and develop quantum algorithms that exploit photonic quantum computing machines for practical applications, following two approaches: adapting protocols designed for qubit-based systems, or directly devising approaches which natively fit for photonic systems.