Thermodynamic properties of perturbed monolayer PbBiI

In this paper, we theoretically investigate the influence of external electric field, Zeeman splitting field, and dilute charged impurity on the thermodynamic features of the PbBiI monolayer. Green's function approach, the Born approximation, and the tight-binding model are employed to address these effects. We find the responses of the electronic heat capacity (HC) and Pauli spin paramagnetic susceptibility (PSPS) to the symmetry breaking originated from the presence of the perturbations. The results show that the electric (Zeeman) field leads to an increase (decrease) in the bulk gap of the system, resulting in a gapless phase at a critical Zeeman field. Correspondingly, HC and PSPS results confirm almost zero responses at the appeared critical Zeeman field. On the other hand, critical impurity characters emerge within the validity regime of the Born approximation. Finally, the combined effects of these perturbations are compared with the findings from the individual ones. © 2022 Elsevier Ltd