Persistent Spin-texture and Ferroelectric Polarization in 2D Hybrid Perovskite Benzylammonium Lead-halide
Fanhao Jia, Shunbo Hu, Shaowen Xu, Heng Gao, Guodong Zhao, Paolo Barone, Alessandro Stroppa, Wei Ren
Abstract
Density functional theory calculations were performed for the electronic and the ferroelectric properties of the bulk and the monolayer benzylammonium lead-halide (BA2PbCl4). Our calculations indicate that both the bulk and monolayer systems display a band gap of ∼3.3 eV (HSE06+SOC) and a spontaneous polarization of ∼5.4 μC/cm2. The similar physical properties of bulk and monolayer systems suggest a strong decoupling among the layers in this hybrid organic–inorganic perovskite. Both the ferroelectricity, through associated structure distortion, and the spin–orbit coupling, through splitting induced in the electronic bands, significantly influence the band gaps. Most importantly, we found for the first time in a two-dimensional hybrid organic–inorganic class of material, a peculiar spin texture topology such as a unidirectional spin–orbit field, which may lead to a protection against spin decoherence.