The field of the invention is that of solid-state laser gyros. One of the
major inherent problems in this technology is that the optical emission
of this type of laser is by nature highly unstable in terms of power. To
reduce this instability, the invention proposes to introduce, into the
cavity, optical gains controlled by the installation of an optical
assembly comprising an anisotropic lasing medium, a first optical element
and a second optical element exhibiting a nonreciprocal effect, each
acting on the polarization of the counterpropagating optical modes, at
least one of these two effects being variable, thus making it possible to
introduce controlled optical gains that depend on the propagation
direction of the counterpropagating optical modes. Several devices are
described and employ either fixed effects of the element that are
combined with variable nonreciprocal effects, or the reverse. These
devices apply in particular to monolithic-cavity lasers.