Spin-dependent optical excitations in LiFeO2

TL;DR

This study investigates the electronic, magnetic, and optical properties of LiFeO2 using advanced theoretical methods, revealing anisotropic excitations, strong spin-polarizations, and potential applications in spintronics and photocatalysis.

Contribution

It provides a comprehensive analysis of LiFeO2's spin-dependent optical excitations, highlighting the role of orbital hybridizations and excitonic effects with detailed theoretical insights.

Findings

Unusual optical transitions with frequency-dependent absorption structures

Identification of prominent plasmon modes via dielectric functions

Optical excitations are anisotropic and significantly influenced by excitonic effects

Abstract

The three-dimensional ternary LiFeO2 compound presents various unusual essential properties. The main features are thoroughly explored by the density functional and 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, the spatial charge densities, the spin-density distributions, and the strong optical responses. The unusual optical transitions cover various frequency-dependent absorption structures, and the most prominent plasmon modes are identified by 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 photo-catalysis applications.