A developing frontier in condensed matter physics is the emergence of novel electromagnetic responses, such as topological and anomalous Hall effect (AHE), in ferromagnetic Weyl semimetals (FM-WSMs). Candidates of FM-WSM are limited to materials that preserve inversion symmetry and generate Weyl crossings by breaking time-reversal symmetry. These materials share three common features: a centrosymmetric lattice, a collinear FM ordering, and a large AHE observed when the field is parallel to the magnetic easy-axis. Here, we present CeAlSi as a new type of FM-WSM, where the Weyl nodes are stabilized by breaking inversion symmetry, but their positions are tuned by breaking time-reversal symmetry. Unlike the other FM-WSMs, CeAlSi has a noncentrosymmetric lattice, a noncollinear FM ordering, and a novel AHE that is anisotropic between the easy- and hard-axes. It also exhibits large FM domains that are promising for both device applications and an interplay between the Weyl nodes and FM domain walls.
@article{arxiv.2006.07943,
title = {A new noncollinear ferromagnetic Weyl semimetal with anisotropic anomalous Hall effect},
author = {Hung-Yu Yang and Bahadur Singh and Jonathan Gaudet and Baozhu Lu and Cheng-Yi Huang and Wei-Chi Chiu and Shin-Ming Huang and Baokai Wang and Faranak Bahrami and Bochao Xu and Jacob Franklin and Ilya Sochnikov and David E. Graf and Guangyong Xu and Yang Zhao and Christina M. Hoffman and Hsin Lin and Darius H. Torchinsky and Collin L. Broholm and Arun Bansil and Fazel Tafti},
journal= {arXiv preprint arXiv:2006.07943},
year = {2021}
}