А.R. Safin - student, Department of generation of oscillations and signals, National Research University "MPEI". E-mail: safin_ansar@mail.ru, arsafin@gmail.com
М.V. Kapranov - Ph.D. (Eng.), professor, Department of generation of oscillations and signals, National Research University "MPEI". E-mail: kapranovmv@mail.ru
N.N. Udalov - Dr.Sci. (Eng.), professor, Department of generation of oscillations and signals, National Research University "MPEI". E-mail: udalovnn@mpei.ru, udalovnn@rambler.ru

Researches in the field of generation of microwave fluctuations by nanosized structures with magnetic multilayers - spin-transfer nano-oscillators (STNO) are actively conducted by large scientific groups. The essential shortcoming limiting practical use of STNO is its low output power (from units of nanowatts for the elementary samples and to tens microwatts for generators with more difficult configuration of layers). Despite a large number of works in the field of phase locking of the STNOs almost important features of dynamics of the elementary system from two generators weren't considered. Need of it is connected with that the modern production technology of STNO ("nanopatterning") doesn't allow to create samples, with completely identical managing directors of parameters (first of all, the sizes). In the theory of nonlinear physics at research of macroscopic oscillators are most often limited to a case of an identical stock on self-excitation. For STNO the stock on generator self-excitation as a part of ensemble can accept and negative values that significantly complicates procedure of research and in modern literature questions of synchronization of such generators aren't considered. In this work features of phase locking of two not-identical STNO interacting at the expense of spin waves in the general ferromagnetic layer are considered. It is shown that distinctions in sizes of two STNO increases a mutual phase locking bandwidth of such a system. This effect is illustrated by 3D-phase portraits on which specifics of transition to an asynchronous mode for ensemble from two STNO with differing radiuses is shown. Thus, the technological dispersion in STNO sizes in some cases can be the positive factor improving synchronous properties of this scheme. At the same time, the noticeable disparate in sizes of partially STNO worsens power indicators of the scheme of addition of power. In this work the effect, being that in a case when a factor of regeneration of one of generators positive, and the second the negative, synchronous working hours of such system are possible was found. The effect of "help" more energetically "strong" STNO to "weaker" is observed.

 

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