The impact of an external electric field on the Rashba effect in two-dimensional hybrid perovskites

Abstract

Two-dimensional (2D) hybrid organic–inorganic perovskites (HOIPs) have aroused extensive research interest in the scientific community for their superior optoelectronic properties and promising applications including light emitting and energy harvesting devices. The Rashba effect is one of the most attractive phenomena in 2D HOIPs for their relatively larger splitting magnitude which could be well applied in spintronic devices. However, it is yet to be fully understood what impacts the external electric field has on the Rashba effect in 2D HOIPs, though this question is significant for the voltage control of optoelectronic and spintronic devices based on 2D HOIPs. In this work, the detailed impacts of the external electric field on the Rashba effect in 2D HOIPs are investigated via first-principles calculations. The structural distortion degree Δθ_X (X = Br, I), the Rashba splitting energy E_R, and the Rashba splitting coefficient α_R with its response rate to the external electric field R_E are calculated for 2D HOIPs including 1–3 L MAPbBr₃, 1 L MAPbI₃, and (PEA)₂PbBr₄ with the external electric field changing range of −0.2 V Å⁻¹ to 0.2 V Å⁻¹. The results could help in better understanding the Rashba effect in 2D HOIPs, provide a practical reference to the voltage control of devices based on 2D HOIPs, and further inspire future research.