  We apply strategy of variational measurement to simplest variant of
dissipative coupling (test mass displacement change transitivity of a single
mirror) and compare it with simplest dispersive coupling (a single mirror as a
test mass, which position changes the phase of reflected wave). We compare a
ponderomotive squeezing in this two kinds of coupling. Also we analyze simplest
variant of combined coupling, in which both dissipative and dispersive
couplings are used, and show that it creates stable optical rigidity even in
case of single pump. We demonstrate that variational measurement can be applied
for combined coupling.

Instrumentation and Detectors;Optics