  We study three kinetic Langevin samplers including the Euler discretization,
the BU and the UBU splitting scheme. We provide contraction results in
$L^1$-Wasserstein distance for non-convex potentials. These results are based
on a carefully tailored distance function and an appropriate coupling
construction. Additionally, the error in the $L^1$-Wasserstein distance between
the true target measure and the invariant measure of the discretization scheme
is bounded. To get an $\varepsilon$-accuracy in $L^1$-Wasserstein distance, we
show complexity guarantees of order $\mathcal{O}(\sqrt{d}/\varepsilon)$ for the
Euler scheme and $\mathcal{O}(d^{1/4}/\sqrt{\varepsilon})$ for the UBU scheme
under appropriate regularity assumptions on the target measure. The results are
applicable to interacting particle systems and provide bounds for sampling
probability measures of mean-field type.
