A rigorous investigation of possible quantum interfaces formed of hybrid components like multiple semiconductor or superconductor few-level qubits interacting with optical micro-/nano-resonators and external electromagnetic fields was proposed. Particular attention was paid to the following aspects: the conversion of photons from the visible domain into microwaves and to the detection of these; the ways to improve the quantum efficiency of various quantum cycled processes in nano-devices, based on quantum thermodynamics laws; and to the non-linear effects in vibrating laser-pumped mirror systems. The objectives of the project were the feasible applications towards sensitive quantum sensors, quantum heat engines or quantum refrigerators, quantum batteries or quantum memory. The proposed objectives were achieved using appropriate analytical methods of theoretical physics like the standard Master Equation Technique, intended to be applied to the systems of regularly/irregularly spaced few-level emitters and which will be modified accordingly to deal with details of the specific task. Appropriate numerical methods were used to describe the complexity of the many-qubit interactions mediated also by various opto- or mechanical resonators, respectively. The obtained results may be applied in modern hybrid nano-photonics technologies with artificial fewlevel qubits. The publishing of the obtained results in various scientific journals of high reputation (such as Physical Review A/B etc.) was expected. The project team consisted of 13 researchers, 4 being under 35, all having already a vast experience of dealing with such research projects in Moldova or abroad. The project team members have published in the last 5 years a series of publications in journals with IF on close topics.