Polaron pattern recognition
in correlated oxide surfaces

Subproject P07

The formation of polarons by charge trapping is pervasive in transition metal oxides. Polarons have been widely studied in binary compounds but comparatively much less so in perovskites.

In P07, we aim to combine advanced first-principles approaches with computer-vision and machine-learning techniques to accelerate and automatize the study of polarons and novel polaron effects in perovskites.
The project has three main pillars: (i) artificial intelligence-aided analysis of experimental ncAFM/STM results (from P02 Diebold, P04 Parkinson) to extract lattice symmetry, surface structure, and chemical composition; (ii) calculation of polaronic configurational energies at different concentrations and temperature using NN; and (iii) identification of unusual types of polarons and polaron-defect complexes in doped perovskites such as spin-, ferroelectric-, Jahn-Teller-, small polarons, and bipolarons.

In the long-term, we plan to establish a fully automatic diagnosis of ncAFM/STM (symmetry, defects, domains) and LEED (diffraction, surface reconstruction) and the construction of a combined experiment & theory database. The research will benefit from two external collaborators and synergy with several experimental (P02, P04) and computational (P03 Kresse, P09 Madsen) TACO partners.

Cesare Franchini
PI

Expertise

Theoretical and computational modeling of quantum materials, in particular transition metal oxides in bulk phases and surfaces, to predict and interpret novel physical effects and states of matter arising from fundamental quantum interactions: electron-electron correlation, electron-phonon coupling, spin-spin exchange, spin-orbit coupling, to name the most relevant ones. The theoretical research is conducted in strong synergy and cooperation with experimental groups.

Methods:

  • Density functional theory, hybrid functionals, GW, BSE
  • First principles molecular dynamics
  • Effective Hamiltonian
  • Diagrammatic quantum Monte Carlo
  • Dynamical mean-field theory
  • Machine learning and computer vision

Applications:

  • Polarons: formation, dynamics, polaron-mediated effects, many-body properties
  • Computational surface science: energetics, reconstructions, surface polarons, polarity effects, adsorption and chemical reactions
  • Quantum magnetism: all-rank multipolar spin-spin interactions beyond Heisenberg exchange
  • Electronic and magnetic phase transitions

Our goals in TACO:

  1. Accelerated study of polaron properties by integrating molecular dynamics and machine learning methods (kernel-ridge regression, standard and convolutional neural-networks
  2. Implementation of automated identification of local structures in atomically resolved images using computer vision methods
  3. Complementing the experimental measurements with extensive first principles modeling of perovskite surfaces.

Team

Cesare Franchini
PI

Michele Reticcioli
co-PI

Matthias Meier
PostDoc

Viktor Birschitzky
PhD Student

Marco Corrias
PhD Student

Florian Ellinger
PhD Student

Publications

Show all

2023

Hematite α-Fe2O3(0001) in Top and Side View: Resolving Long-Standing Controversies about Its Surface Structure

Redondo, Jesús; Michalička, Jan; Kraushofer, Florian; Franceschi, Giada; Šmid, Břetislav; Kumar, Nishant; Man, Ondřej; Blatnik, Matthias; Wrana, Dominik; Mallada, Benjamin; Švec, Martin; Parkinson, Gareth S.; Setvin, Martin; Riva, Michele; Diebold, Ulrike; Čechal, Jan

Hematite α-Fe2O3(0001) in Top and Side View: Resolving Long-Standing Controversies about Its Surface Structure

Journal ArticleOpen Access

In: Advanced Materials Interfaces, no. 2300602, 2023.

Abstract | Links | BibTeX | Tags: P02, P04

Oxygen-Terminated (1 × 1) Reconstruction of Reduced Magnetite Fe3O4(111)

Kraushofer, Florian; Meier, Matthias; Jakub, Zdeněk; Hütner, Johanna; Balajka, Jan; Hulva, Jan; Schmid, Michael; Franchini, Cesare; Diebold, Ulrike; Parkinson, Gareth S.

Oxygen-Terminated (1 × 1) Reconstruction of Reduced Magnetite Fe3O4(111)

Journal ArticleOpen Access

In: vol. 14, no. 13, pp. 3258–3265, 2023.

Abstract | Links | BibTeX | Tags: P02, P04, P07

2022

Surface chemistry on a polarizable surface: Coupling of CO with KTaO 3(001)

Wang, Zhichang; Reticcioli, Michele; Jakub, Zdenek; Sokolović, Igor; Meier, Matthias; Boatner, Lynn A; Schmid, Michael; Parkinson, Gareth S.; Diebold, Ulrike; Franchini, Cesare; Setvin, Martin

Surface chemistry on a polarizable surface: Coupling of CO with KTaO 3(001)

Journal ArticleOpen Access

In: Science Advances, vol. 8, iss. 33, 2022.

Abstract | Links | BibTeX | Tags: P02, P04, P07

Role of Polarons in Single-Atom Catalysts: Case Study of Me1[Au1,Pt1 and Rh1] on TiO2(110)

Sombut, Panukorn; Puntscher, Lena; Atzmüller, Marlene; Jakub, Zdenek; Reticcioli, Michele; Meier, Matthias; Parkinson, Gareth S.; Franchini, Cesare

Role of Polarons in Single-Atom Catalysts: Case Study of Me1[Au1,Pt1 and Rh1] on TiO2(110)

Journal ArticleOpen Access

In: Topics in Catalysis, vol. 65, pp. 1620–1630, 2022.

Abstract | Links | BibTeX | Tags: P04, P07

CO oxidation by Pt2/Fe3O4: Metastable dimer and support configurations facilitate lattice oxygen extraction

Meier, Matthias; Hulva, Jan; Jakub, Zdenek; Kraushofer, Florian; Bobić, Mislav; Bliem, Roland; Setvin, Martin; Schmid, Michael; Diebold, Ulrike; Franchini, Cesare; Parkinson, Gareth S.

CO oxidation by Pt2/Fe3O4: Metastable dimer and support configurations facilitate lattice oxygen extraction

Journal ArticleOpen Access

In: ScienceAdvances, vol. 8, iss. 13, pp. eabn4580, 2022.

Abstract | Links | BibTeX | Tags: P02, P04, P07

2021

Ni-modified Fe3O4(001) surface as a simple model system for understanding the oxygen evolution reaction

Mirabella, Francesca; Müllner, Matthias; Touzalin, Thomas; Riva, Michele; Jakub, Zdenek; Kraushofer, Florian; Schmid, Michael; Koper, Marc T M; Parkinson, Gareth S.; Diebold, Ulrike

Ni-modified Fe3O4(001) surface as a simple model system for understanding the oxygen evolution reaction

Journal ArticleOpen Access

In: Electrochimica Acta, vol. 389, pp. 138638, 2021.

Abstract | Links | BibTeX | Tags: P02, P04, pre-TACO

Unraveling CO adsorption on model single-atom catalysts

Hulva, Jan; Meier, Matthias; Bliem, Roland; Jakub, Zdenek; Kraushofer, Florian; Schmid, Michael; Diebold, Ulrike; Franchini, Cesare; Parkinson, Gareth S.

Unraveling CO adsorption on model single-atom catalysts

Journal Article

In: Science, vol. 371, no. 6527, pp. 375–379, 2021.

Abstract | Links | BibTeX | Tags: P02, P04, P07, pre-TACO

2020

IrO2 Surface Complexions Identified through Machine Learning and Surface Investigations

Timmermann, Jakob; Kraushofer, Florian; Resch, Nikolaus; Li, Peigang; Wang, Yu; Mao, Zhiqiang; Riva, Michele; Lee, Yonghyuk; Staacke, Carsten; Schmid, Michael; Scheurer, Christoph; Parkinson, Gareth S.; Diebold, Ulrike; Reuter, Karsten

IrO2 Surface Complexions Identified through Machine Learning and Surface Investigations

Journal Article

In: Physical Review Letters, vol. 125, no. 20, pp. 206101, 2020.

Abstract | Links | BibTeX | Tags: P02, P04, pre-TACO

Electrochemical Stability of the Reconstructed Fe3O4(001) Surface

Grumelli, Doris; Wiegmann, Tim; Barja, Sara; Reikowski, Finn; Maroun, Fouad; Allongue, Philippe; Balajka, Jan; Parkinson, Gareth S.; Diebold, Ulrike; Kern, Klaus; Magnussen, Olaf M

Electrochemical Stability of the Reconstructed Fe3O4(001) Surface

Journal Article

In: Angewandte Chemie - International Edition, vol. 59, no. 49, pp. 21904–21908, 2020.

Abstract | Links | BibTeX | Tags: P02, P04, pre-TACO

2019

Local Structure and Coordination Define Adsorption in a Model Ir1/Fe3O4 Single-Atom Catalyst

Jakub, Zdenek; Hulva, Jan; Meier, Matthias; Bliem, Roland; Kraushofer, Florian; Setvin, Martin; Schmid, Michael; Diebold, Ulrike; Franchini, Cesare; Parkinson, Gareth S.

Local Structure and Coordination Define Adsorption in a Model Ir1/Fe3O4 Single-Atom Catalyst

Journal ArticleOpen Access

In: Angewandte Chemie - International Edition, vol. 58, no. 39, pp. 13961–13968, 2019.

Abstract | Links | BibTeX | Tags: P02, P04, P07, pre-TACO