The parent compound of high-Tc superconducting cuprates is a unique Mott state consisting of layers of spin-1/2 ions arranged on a square lattice and with a record high antiferromagnetic coupling within the layers. Compounds with similar characteristics have long been searched for. Nickelates and iridates had been proposed as cuprate analogs but so far have not reached a satisfactory similarity. Here we use a combination of experimental and theoretical tools to show that the commercial compound AgF2 is an excellent cuprate analog with remarkably similar electronic parameters to La2CuO4 but larger buckling of planes. Two-magnon Raman scattering reveals a superexchange constant which reaches 70% of that of a typical cuprate. We argue that structures that reduce or eliminate the buckling of the AgF2 planes could have an antiferromagnetic coupling that matches or surpasses the cuprates.
@article{arxiv.1804.00329,
title = {The silver route to cuprate analogs},
author = {Jakub Gawraczyński and Dominik Kurzydłowski and Wojciech Gadomski and Zoran Mazej and Giampiero Ruani and Ilaria Bergenti and Tomasz Jaroń and Andrew Ozarowski and Stephen Hill and Piotr J. Leszczyński and Kamil Tokár and Mariana Derzsi and Paolo Barone and Krzysztof Wohlfeld and José Lorenzana and Wojciech Grochala},
journal= {arXiv preprint arXiv:1804.00329},
year = {2019}
}
Comments
15 pages, 3 figures plus Supplementary Information in ancillary folder