Phase diagram of three dimensional disordered nodal-line semimetals: weak localization to Anderson localization

Abstract

Nodal-line semimetals are new members of the topological materials family whose experimental characterization has seen recent progress using both ARPES and quantum oscillation measurements. Here, we theoretically study the presence of a disorder-induced phase transition in a cubic lattice nodal-line semimetal using numerical diagonalization and spectral calculations. In contrast to the 3D nodal-point semimetals, we found that nodal-line semimetals do not display a stable disordered semimetal phase, as an infinitely weak disorder can lead to a diffusive metal phase. The absence of a semimetal phase is also reflected in the quadratic relationship of the electronic specific heat at low temperatures. Furthermore, we illustrate that a localization transition occurs under the influence of strong disorder, shifting the material from a weakly localized diffusive metal state to an Anderson insulator. This transition is substantiated by calculating the adjacent gap ratio and the typical density of states.