Understanding similarities and differences between the cuprate and nickelate superconductors is drawing intense current interest. Competing charge orders have been observed recently in the undoped infinite-layer nickelates in sharp contrast to the undoped cuprates which exhibit robust antiferromagnetic insulating ground states. The microscopic mechanisms driving these differences remain unclear. Here, using in-depth first-principles and many-body theory based modeling, we show that the parent compound of the nickelate family, LaNiO2, hosts a charge density wave (CDW) ground state with the predicted wavevectors in accord with the corresponding experimental findings. The CDW ground state is shown to be connected to a multi-orbital Peierls distortion. Our study points to the key role of electron-phonon coupling effects in the infinite-layer nickelates.
@article{arxiv.2207.00184,
title = {Peierls distortion driven multi-orbital origin of charge density waves in the undoped infinite-layer nickelate},
author = {Ruiqi Zhang and Christopher Lane and Johannes Nokelainen and Bahadur Singh and Bernardo Barbiellini and Robert S. Markiewicz and Arun Bansil and Jianwei Sun},
journal= {arXiv preprint arXiv:2207.00184},
year = {2023}
}