Cooperative phenomena in the condensed matter were in the center of attention for Nicolae A Enaki in his earlier studies at the Physics Faculty of Moldova State University ( 1975-1980). The interest in the modification of macroscopic polarization of dipoles and quantum peculiarity of emitted photons by excited atomic or molecular ensembles becomes his postgraduate investigation at the radio-physics department, Physics Faculty of Lomonosov State University from Moscow (1981-1985). Here he was focused on the subject of Ph.D. dissertation “Quantum Statistics of superradiance in an extended system of radiators”. After that N. Enaki continues the studies of the quantum statistical properties of radiation in “Single- and two-photon cooperative processes in optics” (the theme of Dr. Habilitatus dissertation, 1993). As a Principal Researcher of the Institute of Atomic Physics, Theoretical Physics Lab. Magurele, Bucharest Romania (1995-1998) he extended the area of interest in the cooperative phenomena of condensed matter and quantum nucleons. He proposed new cooperative effects in the two-photon exchanges between the quantum emitters. This new type of fluorescence consists of broadband radiation pulse and may be ignited by dipole active excited radiators (nuclei, atom, molecules) subsystems so that the decay rate becomes proportional to the cube of numbers of radiators in the system. The new type of coherent effects between the photon pairs and cooperative scattering effects was in the center of attention of Prof. Nicolae Enaki. Many of these effects were proposed to use in communication, holography, and diagnostics. The nonlinear exchange mechanisms between the electrons through the two-phonons taking into consideration peculiarities of nonlinear lattice vibration in solids was used for the description of anomalies in superconductivity phase transitions and Bose-Einstein condensate of cold atoms. As a scientific advisor of "Quantum Optics and Kinetic Process" Lab in the Institute of Applied Physics, Chisinau, R. Moldova he won the long-time project of NATO SPS (2015-2019). During the project, a young researcher team of the laboratory has developed new equipment for the biological decontamination of translucent fluids infected by pathogens (viruses and bacteria). Here was used the cooperative light scattering (including ultraviolet) in quasi-periodical structures of metamaterial formed from fibers or bubbles. The efficient of decontamination equipment is based on the substantial improving the contact surface between the proposed metamaterials and contaminated fluids. His monograph ” Nonlinear Cooperative effects in open quantum systems: entanglement and second-order coherence” published in Nova Science Publishers, NY, USA, 2015, 325 pp, in principle reflect research Interests in the proposed field.