Small Polarons in Transition Metal Oxides

Living reference work entry


The formation of polarons is a pervasive phenomenon in transition metal oxide compounds, with a strong impact on the physical properties and functionalities of the hosting materials. In its original formulation, the polaron problem considers a single charge carrier in a polar crystal interacting with its surrounding lattice. Depending on the spatial extension of the polaron quasiparticle, originating from the coupling between the excess charge and the phonon field, one speaks of small or large polarons. This chapter discusses the modeling of small polarons in real materials, with a particular focus on the archetypal polaron material TiO2. After an introductory part, surveying the fundamental theoretical and experimental aspects of the physics of polarons, the chapter examines how to model small polarons using first-principles schemes in order to predict, understand, and interpret a variety of polaron properties in bulk phases and surfaces. Following the spirit of this handbook, different types of computational procedures and prescriptions are presented with specific instructions on the setup required to model polaron effects.



The authors gratefully acknowledge the support of the Austrian Science Fund (FWF) SFB project VICOM (Grant No. F41) and FWF project POLOX (Grant No. I 2460-N36). The data and analysis presented in this chapter are the results of years-long collaborations on the physics of polarons with the theoretical colleague X. Hao (University of Vienna, now Yanshan University), A. Janotti, and C. Van de Walle (University of California, Santa Barbara) and with the experimental collaborators M. Setvin and M. Schmid (Surface Science Group @ TU Wien). Their invaluable help and stimulating ideas were essential to develop the research on polarons discussed in this work.


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Authors and Affiliations

  1. 1.University of ViennaViennaAustria
  2. 2.Institute of Applied PhysicsTechnische Universität WienViennaAustria
  3. 3.Faculty of Physics and Center for Computational Materials ScienceUniversity of ViennaViennaAustria

Section editors and affiliations

  • Cesare Franchini
    • 1
  • Bilge Yildiz
    • 2
  1. 1.Faculty of Physics and Center for Computational Materials ScienceUniversity of ViennaViennaAustria
  2. 2.Materials Science and EngineeringMassachusetts Institute of TechnologyCambridgeUSA

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