A phenomenological model of the fine structure emergence in microwave power spectra of an autonomous phaser

In this work, we propose a phenomenological model of the FS emergence in the phaser generation spectra, which takes place in the absence of any external forcing of the spin-phonon active system. In other words, FS arises spontaneously, without those or that influence from outside. Moreover, the FS emergency is usually the first stage of very complex spatio-temporal structures development in phaser systems, so it is an important task to understand the nature of the pointed first stage.