Exploring materials for tunable non-linear Hall effects

 In recent years, it has been discovered that inversion symmetry broken systems can exhibit

non-linear Hall effects even under time-reversal symmetric conditions [1]. The underlying quantum objects leading to this phenomena are the moments of the Berry curvature, termed the Berry curvature multipoles. This opens up avenues for exploring fundamental physics and possible applications [2,3]. However, despite such promise, the Berry curvature multipole induced non-linear Hall effect has been experimentally realized only in a handful of materials. It is, therefore, of vital importance to find materials with large and controllable Berry curvature multipoles.

In this talk, I will give examples from our work where such a controllable Berry curvature dipole has been predicted. First, we propose Janus monolayers of transition metal dichalcogenides as a promising materials platform to explore the non-linear Hall effect and Berry curvature dipole physics [4]. Here the topology and the Berry curvature dipole are tunable by chemical composition. Second, we discover a giant non-linear Hall effect in the elemental buckled honeycomb lattices -- silicene, germanene, and stanene [5]. In this case, the Berry curvature dipole is tunable by a transverse electric field which breaks inversion

symmetry. We demonstrate that the electric field induced topological phase transitions are associated with a giant Berry curvature dipole near the critical field. Finally, I will highlight our ongoing work on detection of chirality and ferroelectricity using Berry curvature multipoles [6].

 

[1] I. Sodemann and L. Fu, Phys. Rev. Lett. 115, 216806 (2015).

[2] Z. Du, H.-Z. Lu, and X. Xie, Nature Reviews Physics 3, 744 (2021).

[3] A. Bandyopadhyay, N. B. Joseph, and A. Narayan, arXiv:2401.02282 (2024).

[4] N. B. Joseph, S. Roy, and A. Narayan, Materials Research Express 8, 124001 (2021).

[5] A. Bandyopadhyay, N. B. Joseph, and A. Narayan, 2D Materials 9, 035013 (2022).

[6] N. B. Joseph et al., in preparation.