Spin-dependent Optical Excitations in LiFeO₂

Abstract

The three-dimensional ternary LiFeO 2 compound presents various unusual properties. The main features are thoroughly explored by using many-body perturbation theory. The concise physical/chemical picture, the critical spin polarizations, and orbital hybridizations in the Li−O and Fe−O bonds are clearly examined through geometric optimization, quasi-particle energy spectra, spin-polarized density of states, spatial charge densities, spin-density distributions, and strong optical responses. The unusual optical transitions cover various frequency-dependent absorption structures, and the most prominent plasmon modes are identified from the dielectric functions, energy loss functions, reflectance spectra, and absorption coefficients. Optical excitations are anisotropic and strongly affected by excitonic effects. The close combinations of electronic, magnetic, and optical properties allow us to identify the significant spin polarizations and orbital hybridizations for each available excitation channel. The lithium ferrite compound can be used for spintronic and photocatalysis applications.

Optical excitations of graphene-like materials: group III-nitrides

“…The observed increase in the electronic band gap can be attributed to the electron–electron self-energy effects, as extensively discussed in numerous prior publications. 75–78 The GW gap (called a quasi-particle gap) agrees closely with the electronic gap measured in scanning tunneling spectroscopy (STS) experiments. This means that the GW gap is comparable to the experimental results.…”

“…The observed increase in the electronic band gap can be attributed to the electron-electron self-energy effects, as extensively discussed in numerous prior publications. [75][76][77][78] The GW gap (called a quasi-particle gap) Fig. 6 (a-d) Charge density distributions and band decomposed charge densities of the BN, AlN, GaN, and InN monolayers, respectively.…”

Electronic and Optical Properties of CsGeX3 (X= Cl, Br, and I) Compounds

“…Although the excitonic effects in the broad energy range of materials, , including CsGeX 3 , have been qualitatively estimated by effective mass models, the quantitative description of these bound states is rather limited. There are few works that relied on ab initio Bethe–Salpeter equation (BSE) calculations; ,− however, the formation as well as the nature of the excitonic states has not been elucidated yet.…”

First-principles simulation insights of electronic and optical properties: Li6PS5Cl system

“…In terms of theory, it is known that the rst-principles calculations could give many expected results on electronic and optical properties of emerging materials [23][24][25][26][27] and agree well experimental measurements. However, we detected that investigation of rst-principles calculations on this compound is still rather limited.…”