Identification of large polarons and exciton polarons in rutile and anatase polymorphs of titanium dioxide
arXiv:2411.15344 · doi:10.1073/pnas.2414203121
Abstract
Titanium dioxide (TiO2) is a wide-gap semiconductor with numerous applications in photocatalysis, photovoltaics, and neuromorphic computing. The unique functional properties of this material critically depend on its ability to transport charge in the form of polarons, namely narrow electron wavepackets accompanied by local distortions of the crystal lattice. It is currently well established that the most important polymorphs of TiO2, the rutile and anatase phases, harbor small electron polarons and small hole polarons, respectively. However, whether additional polaronic species exist in TiO2, and under which conditions, remain open questions. Here, we provide definitive answers to these questions by exploring the rich landscape of polaron quasiparticles in TiO2 via recently developed ab initio techniques. In addition to the already known small polarons, we identify three novel species, namely a large hole polaron in rutile, a large quasi-two-dimensional electron polaron in anatase, and a large exciton polaron in anatase. These findings complete the puzzle on the polaorn physics of TiO2 and pave the way for systematically probing and manipulating polarons in a broad class of complex oxides and quantum materials.
References in corpus (31)
- Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
- Advanced capabilities for materials modelling with Quantum ESPRESSO
- Electron-phonon interactions from first principles
- BerkeleyGW: A Massively Parallel Computer Package for the Calculation of the Quasiparticle and Optical Properties of Materials and Nanostructures
- A direct view at excess electrons in TiO rutile and anatase
- First-principles calculations of charge carrier mobility and conductivity in bulk semiconductors and two-dimensional materials
- Towards predictive many-body calculations of phonon-limited carrier mobilities in semiconductors
- Tunable polaronic conduction in anatase TiO2
- Self-Energy and Excitonic Effects in the Electronic and Optical Properties of TiO2 Crystalline Phases
- Tailoring the nature and strength of electron-phonon interactions in the SrTiO(001) two-dimensional electron liquid
- Strongly bound excitons in anatase TiO2 single crystals and nanoparticles
- Polaronic metal state at the LaAlO3/SrTiO3 interface
- Origin of the crossover from polarons to Fermi liquids in transition metal oxides
- Ab initio theory of polarons: formalism and applications
- Polarons from first principles, without supercells
- Holstein polaron in a valley-degenerate two-dimensional semiconductor
- Exciton-Phonon Interaction and Relaxation Times from First Principles
- Emergence of Frohlich polaron from interlayer electron-phonon coupling in van der Waals heterostructure
- Polarons in two-dimensional atomic crystals
- First-Principles Supercell Calculations of Small Polarons with Proper Account for Long-Range Polarization Effects
- Unified approach to polarons and phonon-induced band structure renormalization
- Excitonic polarons and self-trapped excitons from first-principles exciton-phonon couplings
- Ab initio calculation of carrier mobility in semiconductors including ionized-impurity scattering
- Ab initio self-consistent many-body theory of polarons at all couplings
- Efficient Ab Initio Calculations of Electron-Defect Scattering and Defect-Limited Carrier Mobility
- Unified ab initio description of Fröhlich electron-phonon interactions in two-dimensional and three-dimensional materials
- Theory of excitonic polarons: From models to first-principles calculations
- Discovery of the soft electronic modes of the trimeron order in magnetite
- Phonon-Dressed Two-Dimensional Carriers on the ZnO Surface
- Fröhlich polaron effective mass and localization length in cubic materials: degenerate and anisotropic electronic bands
- Facile ab initio approach for self-localized polarons from canonical transformations