The generation of an electromagnetic field by oscillators in an open resonator is discussed in a one-dimensional approximation. In this case, the development of the so-called dissipative instability the dissipative generation regime. Such an instability with the generation of electromagnetic oscillations arises when the decrement of oscillations in an open resonator in the absence of oscillators turns out to be greater than the increment of the resulting instability of the system of oscillators placed in this resonator. It is assumed that the oscillators do not interact with each other, and only the resonator field affects their behavior. If the resonator field is absent or small, the superradiance regime is possible, when the radiation of each oscillator is essential and the field in the system is the sum of all the eigenfields of the oscillators. In the dissipative regime of instability generation, the system of oscillators is synchronized by the induced resonator field. The synchronization of the oscillators in the superradiance mode owes its existence to the integral field of the entire system of oscillators. With a weak nonlinearity of the oscillators, a small initiating external field is required to excite the generation regime. It is noteworthy that the maximum value of the superradiance field is approximately two times less than the maximum field that the same particles could generate if they were at the same point. In all cases, for a given open resonator, the superradiance field turned out to be somewhat larger than the resonator field. Nevertheless, for the same resonator, the increments and attainable field amplitudes in both cases are of the same order of magnitude.
We apply the well-known concept of spontaneous and stimulated emission to some nonlinear processes in plasma. The consideration of beam–plasma instability in this approach allows us not only to obtain an increment of the instability and other important characteristics by a non-traditional method but also to study in detail the initial stage of the instability, when a noise caused by spontaneous emission has a great influence on further dynamics of the system. Another interesting example of the considered method is the three-wave interaction of ion-sonic waves in plasma. We have shown that oscillations generated by nonlinear currents at combined frequencies demonstrate all the characteristics of spontaneous and stimulated emission. In both cases, we derived the equations for the intensity of emitting waves in a form that is similar to equations obtained in the traditional theory of spontaneous and stimulated emission.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.