Solid-State Physics Perspective on Hybrid Perovskite Semiconductors

In this review we examine recent theoretical investigations on 2D and 3D hybrid perovskites (HOPs) that combine classical solid-state physics concepts and density functional theory (DFT) simulations as a tool for studying their optoelectronic properties. Such an approach allows one to define a new class of semiconductors, where the pseudocubic high-temperature perovskite structure plays a central role. Bloch states and, k.p. Hamiltonians yield new insight into the influence of lattice distortions, including loss of inversion symmetry, as well as spin-orbit coupling. Electronic band folding and degeneracy, effective masses, and optical absorption are analyzed. Concepts of Bloch and envelope functions, as well as confinement potential, are discussed in the context of layered HOP and 3D HOP heterostructures. Screening and dielectric confinements are important for room-temperature optical properties of 3D and layered HOP, respectively. Nonradiative Auger effects are analyzed for the first time close to the electronic band gap of 3D hybrid perovskites.