On certain isogenies between K3 surfaces

We will prove that there are infinitely many families of K3 surfaces which both admit a finite symplectic automorphism and are (desingularizations of) quotients of other K3 surfaces by a symplectic automorphism. These families have an unexpectedly high dimension. We apply this result to construct ``special'' isogenies between K3 surfaces which are not Galois covers between K3 surfaces but are obtained by composing cyclic Galois covers. In the case of involutions, for any $ nin mathbb{N}_{>0}$ we determine the transcendental lattices of the K3 surfaces which are $ 2^n:1$ isogenous (by the mentioned ``special'' isogeny) to other K3 surfaces.