Characteristic singular behaviors of nodal-line materials emerging in orbital magnetic susceptibility and Hall conductivity

The bulk properties of nodal-line materials have been an important research topic in recent years. In this paper, we study the orbital magnetic susceptibility and the Hall conductivity of nodal-line materials using the formalism with thermal Green's functions and find characteristic singular behaviors of them. It is shown that, in the vicinity of the gapless nodal line, the orbital magnetic susceptibility shows a 6-function singularity and the Hall conductivity shows a step-function behavior in their chemical potential dependencies. Furthermore, these singular behaviors are found to show strong field-angle dependencies corresponding to the orientation of the nodal line in the momentum space. These singular behaviors and strong angle dependencies will give clear evidence for the presence of the nodal line and its orientation and can be used to experimentally detect nodal-line materials.

Automated summary

This study investigates the orbital magnetic susceptibility and the Hall conductivity of nodal-line materials, revealing their characteristic singular behaviors under certain conditions. These behaviors can serve as clear evidence for the presence of nodal-line materials and their orientation in experimental detection.