Atomic Structure, Lattice Properties and Phase Transitions
Nonlinear Hall effect in Chiral Non-centrosymmetric RuGaSi systems
12:06 pm – 12:18 pmThe chiral symmetry of the quantum materials (QMs) can lead to various exotic quantum phenomena, including the topological Hall effect, planar Hall effect, nonlinear Hall effect (NLHE), etc. This great promise has not been realized due to the poor understanding of the relationship between chiral symmetry and the different properties of QMs. In this work, we carried out a systematic theoretical study to understand the origin of NLHE of newly synthesized ordered Ru7Ga6Si6 and disordered Ru7Ga6.2Si5.8. To overcome the computational modeling challenges of the disordered systems, we have considered three ordered chiral structures: Ru7Ga6Si6, Ru7Ga10Si2, and Ru7Ga2Si10. The dynamical stability calculations reveal that Ru7Ga6Si6 and Ru7Ga10Si2 are dynamically stable. Based on the outcome of the previous step, we studied the electronic properties of stable structures. We found that Ru7Ga6Si6 is a direct band gap semiconductor while Ru7Ga10Si2 is metallic. The chiral space group geometry analysis indicated that the non-vanishing Berry curvature contributed to the non-zero Berry Curvature Dipole moment (BCDM), ultimately yielding the NLHE in a harmonically oscillating electric field. The above findings provide insight into the effect of chirality on QMs properties.