The first Weyl semimetal was recently discovered in the NbP class of compounds. Although the topology of these novel materials has been identified, the surface properties are not yet fully understood. By means of scanning tunneling spectroscopy, we find that NbPs (001) surface hosts a pair of Dirac cones protected by mirror symmetry. Through our high resolution spectroscopic measurements, we resolve the quantum interference patterns arising from these novel Dirac fermions, and reveal their electronic structure, including the linear dispersions. Our data, in agreement with our theoretical calculations, uncover further interesting features of the Weyl semimetal NbPs already exotic surface. Moreover, we discuss the similarities and distinctions between the Dirac fermions here and those in topological crystalline insulators in terms of symmetry protection and topology.
@article{arxiv.1711.05000,
title = {Mirror protected Dirac fermions on a Weyl semimetal NbP surface},
author = {Hao Zheng and Guoqing Chang and Shin-Ming Huang and Cheng Guo and Xiao Zhang and Songtian Zhang and Jiaxin Yin and Su-Yang Xu and Ilya Belopolski and Nasser Alidoust and Daniel S. Sanchez and Guang Bian and Tay-Rong Chang and Titus Neupert and Horng-Tay Jeng and Shuang Jia and Hsin Lin and M. Zahid Hasan},
journal= {arXiv preprint arXiv:1711.05000},
year = {2017}
}