  We discuss the influence of Young's modulus temperature dependence on the
number of parametrically unstable modes in a Fabry-Perot cavity of Advanced
LIGO interferometer. Some unstable modes may be suppressed by changing the
mirror's temperature due to temperature dependence of Young's modulus. Varying
the temperature of the mirrors we can change their frequencies of the elastic
modes; it, in turn, can change the number of unstable modes, leading to
nonlinear effect of parametric oscillatory instability. The determination of
the optimal values of the temperature variations for some elastic modes to
reduce the number of unstable modes is fulfilled. Both new "fine tuning"
supression method of parametric instability and radius of curvature(ROC) change
method in the next generation of gravitational wave detectors are discussed.
The applications of this method in cryogenic detectors like LIGO Voyager or
Einstein Telescope are proposed.
