Researchers linked to the Materials Institute of the USC, iMATUS, (from the Quantum Materials and Photonics Research Laboratory) participate under the direction of Jesús Liñares Beiras, in the so-called Quantum Communications Program within the Complementary R&D&I Plans of the Recovery, Transformation and Resilience Plan financed by the European Union, NextGeneration, and complemented with funds from the Xunta de Galicia (Galician Quantum Technologies Pole). This participation focuses on the development of photonic devices for the generation, self-compensation and measurement of quantum states of light (superposition of one photon or qudits, biphoton, entangled…) preferably oriented to quantum cryptography systems (QKD) in free space and fiber optics, also applicable to specific purpose quantum processing and quantum sensor metrology. Diffractive optical elements (EODs) and passive integrated photonic circuits (IFCs) will be developed mainly (without prejudice to tests with modular systems) manufactured with ion exchange technology (IONEX) in glass, which microstructures glass substrates thus allowing the realization of EODs and CFIs. The EODs manufactured by IONEX are very robust and compatible with modular systems for QKD in free space. As for the CFIs, they are also highly compatible with optical fibers for QKD, cheap to manufacture, and their passive nature (there is no modulation) eliminates energy consumption and makes them immune to side-channel cryptographic attacks. The experience of these researchers in said technology is extensive and they have just obtained, already within this program, significant experimental results on quantum measurement devices (PVM and POVM Projects) integrated by means of IONEX K/Na in soda-lime type glass for its use in quantum communications systems (QKD) (https://doi.org/10.1109/JLT.2022.3189206). The group’s experience in superconducting materials will also allow exploring possible superconducting nanostructures compatible with integrated photonic circuits (hybrid integration) that implement the last stage of the process: the detection of a single photon, or even the detection of the number of photons working close to the critical stream.