Observation of three-state nematicity in the triangular lattice antiferromagnet Fe$_{1/3}$ NbS$_2$

Autor: Little, Arielle, Lee, Changmin, John, Caolan, Doyle, Spencer, Maniv, Eran, Nair, Nityan L., Chen, Wenqin, Rees, Dylan, Venderbos, Jörn W. F., Fernandes, Rafael, Analytis, James G., Orenstein, Joseph
Rok vydání: 2019
Předmět:
Zdroj: Nature Materials (2020)
Druh dokumentu: Working Paper
DOI: 10.1038/s41563-020-0681-0
Popis: Nematic order is the breaking of rotational symmetry in the presence of translational invariance. While originally defined in the context of liquid crystals, the concept of nematic order has arisen in crystalline matter with discrete rotational symmetry, most prominently in the tetragonal Fe-based superconductors where the parent state is four-fold symmetric. In this case the nematic director takes on only two directions, and the order parameter in such "Ising-nematic" systems is a simple scalar. Here, using a novel spatially-resolved optical polarimetry technique, we show that a qualitatively distinct nematic state arises in the triangular lattice antiferromagnet Fe$_{1/3}$NbS$_2$. The crucial difference is that the nematic order on the triangular lattice is a Z$_3$, or three-state Potts-nematic order parameter. As a consequence, the anisotropy axes of response functions such as the resistivity tensor can be continuously re-oriented by external perturbations. This discovery provides insight into realizing devices that exploit analogies with nematic liquid crystals.
Comment: The main text is 16 pages, including 5 figures and references. Supplementary information is appended at the end of the article
Databáze: arXiv