Over the last decade, halide perovskites (HP) have truly emerged as efficient optoelectronic materials and show the promise of exhibiting nontrivial topological phases. Since the bandgap is one of the deterministic factors for these quantum phases, here, using first-principle methods and the model Hamiltonians, we present a comprehensive electronic structure study for centrosymmetric and noncentrosymmetric halide Perovskites. We have developed a minimal basis set based generalized Slater-Koster tight binding Hamiltonian which can explain the bulk and surface electronic structure of these systems. Our study shows that, under the uniform pressure or strain, a system with inversion symmetry transform from trivial insulating phase to non-trivial topological insulating phase with protected Dirac states at the surface, while a system without inversion symmetry, contains an invariant surface Dirac circle. A quasi-degenerate perturbation approach enables us to describe polarized field driven band structures and unique topological phases such as accidental Dirac semimetallic rings in the bulk, for the universal class of Halide perovskites. The spin textures obtained through this theoretical model captures minute effects of polarization and hence can be used as a modern tool to determine the polarized field directions, which have significant influence on spinorbitronics and optoelectronics applications.

KEYWORDS: Halide Perovskites; Model Hamiltonian; Non-trivial topology; pressure and strain; Inversion symmetry breaking field; Ferroelectric polarization; Rashba spin-orbit coupling; Spin texture.