Terahertz nonlinear optics of chiral semimetals RhSn, HfSn, and PdGaYuewen Gao, Toshiaki Iitaka and Zhi LiEur. Phys. J. B, 94 5 (2021) 95DOI: https://doi.org/10.1140/epjb/s10051-021-00093-z