  We study the potential of adaptive optics (AO) to protect entanglement of
high-dimensional photonic orbital-angular-momentum (OAM) states against
turbulence-induced phase distortions. We demonstrate that AO is able to reduce
crosstalk among the OAM modes and, consequently, the entanglement decay as well
as photon losses. A test of the AO-stabilized output state against
high-dimensional Bell inequalities shows that the transmitted entanglement
allows for secure communication, even in the strong scintillation regime.
