  This is a part of an overview of my early studies on nonlinear spin-phonon
dynamics in solid state optical-wavelength phonon lasers (phasers) started in
1984. The main goal of this work is a short description and a qualitative
analysis of experimental data on low-frequency nonlinear resonances revealed in
a nonautonomous ruby phaser. Under phaser pumping modulation near these
resonances, an unusual kind of self-organized motions in the ruby spin-phonon
system was observed by me in 1984 for the first time. The original technique of
optical-wavelength microwave-frequency acoustic stimulated emission (SE)
detection and microwave-frequency power spectra (MFPS) analysis was used in
these experiments (description of the technique see: D.N.Makovetskii, Cand.
Sci. Diss., Kharkov, 1983). The real time evolution of MFPS was studied using
this technique at scales up to several hours. The phenomenon of the
self-organized periodic alternation of SE phonon modes was experimentally
revealed at hyperlow frequencies from about 0.1 Hz to 0.001 Hz and less (for
the phaser pumping modulation at approximately 10 Hz). The nature of this
phenomenon was investigated by me later in details (see:
arXiv:cond-mat/0303188v1 ; arXiv:cond-mat/0410460v1 ; Tech. Phys. Letters,
2001, Vol.27, No.6, P.511-514 ; Tech. Phys., 2004, Vol.49, No.2, P.224-231).
