On Spectral multiplier theorem for sub-Laplacians with drift on Métivier groups

In this paper, we prove a spectral multiplier theorem for sub-Laplacians with drift on Métivier groups. We improve the result of [Martini, Ottazzi and Vallarino, Rev. Mat. Iberoam, 2019] in case of Métivier groups, by reducing the required smoothness condition on the multiplier function from homogeneous dimension to the topological dimension of the underlying group.