Giant Rashba splitting in 2D organic-inorganic halide perovskites measured by transient spectroscopies

Abstract

Transient and CW spectroscopies unravel giant Rashba splitting in 2D hybrid perovskite multilayers.

Halogen in materials design: Fluoroammonium lead triiodide (FNH3PbI3) perovskite as a newly discovered dynamical bandgap semiconductor in 3D

“…An analogous result is also obtained for c‐CH 3 NH 3 PbI 3 (Table ). These are in agreement with the results of similar other studies reported for c‐CH 3 NH 3 PbI 3 …”

“…A number of recent studies indicate that spin‐orbit coupling (SOC) can split the doubly spin‐degenerate valence and conduction band edges in noncentrosymmetric compounds . As expected, and for the pseudocubic polymorphs such as those in (A) and (B) of Figure , the inversion symmetry is broken due to the displacements of the Pb atom from the center of the PbI octahedra.…”

“…Because of this, the spin‐degenerate parabolic edge corresponding to the conduction/valence band is split into two spin‐polarized bands that are shifted with respect to each other in k ‐space. This is connected with Rashba band splitting and has a strong dependence on Z 2 , where Z is the atomic number . A result of this is that the electron (and/or hole) dispersion relationship can now be described by the relationship given by: , where is the Rashba splitting parameter.…”

Spintronics of Hybrid Organic–Inorganic Perovskites: Miraculous Basis of Integrated Optoelectronic Devices

“…Theoretical calculations based on DFT and experiments based on transient spectroscopy methods show that Rashba splitting occurs on a huge scale in 2D HOPs, where the energy splitting is (40 ± 5) meV and the Rashba parameter is (1.6 ± 0.1)eV Å. These findings also indicate that the 2D HOPs have a broad range of application prospects in spintronics, which is similar to the prospects of 3D HOPs. This research will pave the way toward new optoelectronic device designs based on 2D HOPs.…”

“…The valence band peak features a maximum 0.16 eV splitting depth, which occurs at k = 0.043 Å −1 . Another study in 2017 applied transient and steady‐state light modulation‐based spectral techniques to measure the exciton transitions and the free carrier absorption . The observed continuum band splitting reached ≈1.6 eV Å −1 in the 2D layered (C 6 H 5 C 2 H 4 NH 3 ) 2 PbI 4 perovskite, which was a considerably larger value when compared with previous work.…”