Signatures of topological anisotropic Anderson transition in a class-D nodal-line semimetal

We propose a two-band tight-binding model of topological nodal-line Weyl semimetal on the cubic lattice, which belongs to the symmetry class D of the Altland-Zirnbauer classification [1]. By studying disorder-driven quantum phase transitions of the model, we observed signatures of a quasilocalized phase and topological anisotropic Anderson transition, which had been universally observed in the chiral classes with weak topological index [2]. Thereby the metal phase and the Anderson localized phase are intervened by the quasilocalized phase that shows metallic behavior in the topological direction while insulating behavior in the other directions [2]. We investigate the possibility of the two-step phase transition and associated criticalities in this class-D model compared to our previous results of another model [3], and discuss its relation to the topological index and the underlying mechanism in contrast with the chiral classes.

[1] A. Altland and M. R. Zirnbauer, Phys. Rev. B 55, 1142 (1997).

[2] Z. Xiao, K. Kawabata, X. Luo, T. Ohtsuki, and R. Shindou, Phys. Rev. Lett. 131, 056301 (2023).

[3] T. Wang, T. Ohtsuki, and R. Shindou, Phys. Rev. B 104, 014206 (2021).