We study the response of one-dimensional liquid 4He to weak perturbations relying on the dynamical structure factor, S(q,ω), recently obtained via ab-initio techniques [Phys. Rev. Lett. 116, 135302 (2016)]. We evaluate the drag force, Fv, experienced by an impurity moving along the system with velocity v and the static response function, χ(q), describing the density modulations induced by a periodic perturbation with wave vector q.
@article{arxiv.1607.05301,
title = {Linear response of one-dimensional liquid $^4$He to external perturbations},
author = {M. Motta and G. Bertaina and E. Vitali and D. E. Galli and M. Rossi},
journal= {arXiv preprint arXiv:1607.05301},
year = {2016}
}