In supersymmetric models with nonzero Majorana neutrino mass, the sneutrino
and antisneutrino mix, which may lead to same sign dilepton signals in future
collider experiments. We point out that the anomaly-mediated supersymmetry
breaking scenario has a good potential to provide an observable rate of such
signals for the neutrino masses suggested by the atmospheric and solar neutrino
oscillations. The sneutrino mixing rate is naturally enhanced by
m_{3/2}/m_{\tilde{\nu}}={\cal O}(4\pi/\alpha) while the sneutrino decay rate is
small enough on a sizable portion of the parameter space. We point out also
that the sneutrino-antisneutrino mixing can provide much stronger information
on some combinations of the neutrino masses and mixing angles than neutrino
experiments.Comment: Revtex, 13 pages, 2 figure
