Gravitomagnetic effects originates from the rotation of the source of the
gravitational field and from the rotational features of the observers' frame.
In recent years, gravitomagnetism has been tested by means of its impact on the
precession of LAGEOS orbits and on the precession of spherical gyroscopes in
the GP-B experiment. What we suggest here is that light can be used as a probe
to test gravitomagnetic effects in an terrestrial laboratory: the proposed
detector consists of large ring-lasers arranged along three orthogonal axes.Comment: 3 pages, in "QSO astrophysics, fundamental physics, and astrometric
cosmology in the Gaia era" Porto-Portugal, June 6-9, 2011, Editors: S. Anton,
M. Crosta, M.G. Lattanzi and A. Andrei. Memorie della Societ\`a Astronomica
Italiana, Vol. 83 (2012
