Effective mass of heavy, light, and spin split-off band electron and hole g-factor in cubic perovskite materials

Abstract

Analytical expressions for the effective mass of heavy, light, and spin split-off electrons are obtained by diagonalizing the k⋅p Hamiltonian for cubic perovskite crystal structures and used to calculate these in nine perovskite materials. An expression for the effective hole g-factor is also derived and calculated in these perovskites. The calculated effective mass of heavy electrons ranges from 1.619 m0 to 0.201 m0, of light electrons from 0.357 m0 to 0.146 m0, and of spin split-off electrons from 0.584 m0 to 0.169 m0. It is found that Cl- and Pb-based perovskite materials have larger heavy, light, and spin split-off electron effective masses. It is also found that the effective g-factor increases with the atomic size, from Cl to I, for the series CsSnX3(X=Cl,Br,I).

Ligand Coverage and Exciton Delocalization Control Chiral Imprinting in Perovskite Nanoplatelets

“…S2) indicates that the conduction band minimum (CBM) is comprised mainly of Pb p atomic orbitals and that the valence band maximum (VBM) is comprised mainly of Pb s and halide p orbitals, consistent with earlier studies. 67,68 The perovskite electronic structure produces a direct bandgap and strong optical transitions. 67,68 The energy separation between the two lowest-energy optical transitions in the absorbance spectra for Br NPLs (Figure 2C) is consistent with the computed absorption coefficients of the model perovskite NPL in vacuum (see Figure S3).…”

“…67,68 The perovskite electronic structure produces a direct bandgap and strong optical transitions. 67,68 The energy separation between the two lowest-energy optical transitions in the absorbance spectra for Br NPLs (Figure 2C) is consistent with the computed absorption coefficients of the model perovskite NPL in vacuum (see Figure S3). For the Br NPLs, our computed absorption coefficients show a lowest energy absorption at 534 nm, which is at longer wavelength than is measured for the NPLs.…”

An Ab Initio Study of Clusters as Building Blocks for Crystals: From Prussian Blue Analogs to Hybrid Perovskites

“…The best photovoltaic materials have much lower effective masses: and for Si, [ 63 ] and for Ge, [ 63 ] and for GaAs, [ 63 ] 0.146 m 0 for CH 3 NH 3 PbI 3 . [ 64 ] However, our values are comparable to those of some of the best photocatalysts: and , depending on the direction, for anatase TiO 2 , [ 65 ] for rutile TiO 2 , [ 66 ] and for hematite α − Fe 2 O 3 , [ 67 ] for SrTiO 3 . [ 68 ]…”

Intersubband Transitions in Lead Halide Perovskite-Based Quantum Wells for Mid-Infrared Detectors

“…19 The top two conduction bands in Figure 2a represent the light electron (LE) and heavy electron (HE) states, while the bottom of the conduction band is the split-off (SO) state with a spin-split off energy Δ SO of 1.5 eV for CsPbBr 3 . 20 This is in stark contrast to the band structures observed in common III− V semiconductors (Figure 2b) that consist of an s-like conduction band and a valence band comprised of a heavy hole (HH), a light hole (LH), and a SO state. In the following discussions, we deliberately invert the band structures of the perovskite-based QWs in the y-direction to make direct comparison to conventional III−V systems as demonstrated in Figure 2b more straightforward.…”

“…Due to the strong spin–orbit coupling (SOC) in CsPbX 3 perovskites, the well-known Pb 6p orbitals convert to a singlet state at the bottom of conduction band (pink curve in Figure a) and a 3-fold degenerate triplet state with the degeneracy multiplying by 2 considering spin . The top two conduction bands in Figure a represent the light electron (LE) and heavy electron (HE) states, while the bottom of the conduction band is the split-off (SO) state with a spin-split off energy Δ SO of 1.5 eV for CsPbBr 3 . This is in stark contrast to the band structures observed in common III–V semiconductors (Figure b) that consist of an s-like conduction band and a valence band comprised of a heavy hole (HH), a light hole (LH), and a SO state.…”