Journal of Experimental Physics

The quenching of the fluorescence of active dopant (Nd3+) by randomly distributed quenchers (–OH) positioned in the volume of the NPs is a major dissipative channel that directly impacts the quality of the nanoparticles as fluorescent agent in the near IR spectral range. First, a basic understanding of the quenching mechanism has direct practical value for optimization of their efficiency. Second, the fluorescence kinetic studies provide information on the structure of a system and the types of physical interactions that are realized in the process of energy migration and dissipation of optical excitation. In view of the foregoing, the reliable and very sensitive method for the quality control of the fluorescent nanoparticles based on the analysis of the kinetics of impurity quenching, “an energy transfer probing”, is very perspective.

It is well known that the experiment will always say yes or no. Theory only will say "maybe." Experiment always requires time and investment. Enough theory to simply lie back on the couch. For the experiment often requires sophisticated ingenuity. The theory relies on the same fundamental laws, for example, the theory of relativity or quantum mechanics. However, the direct applicability of fundamental laws is often impossible due to the mathematical difficulties. Me in my scientific activity, to describe the results of measurements be used various ways to address emerging challenges. Briefly describe some of them.

This paper presents the results of experimental measurements of magnetic properties of thin NiFe films after irradiation with nanosecond laser pulses. The results showed that there is an optimal energy in the laser pulse, at which the magnetic film characteristics vary the most. For the film of 500 nm thick at magnetic susceptibility ? for a Nd:YAG laser at ?=1064 nm increased almost 3 times, and the coercive force Hc decreased about two. For the excimer laser at ?=248 nm, we have received an increase in the magnetic susceptibility ? almost ten times while a decrease in the coercive force Hc was 5-6 times. The results suggest the importance of non-thermal effects of laser radiation in the process of changing the structure and magnetic properties of magnetic films. All this shows that with the help of laser radiation it is possible to form a regular structure of nanoislands in thin magnetic nanocrystalline films.