Theorie und Modellierung von Polaronen - Einzelansicht

The lecture starts at 4.15 p.m. It will be both in-person and streamed online using zoom:

join zoom meeting
https://uni-jena-de.zoom.us/j/64486433767

Meeting-ID: 644 8643 3767
code: 034314

Suggested reading:
Cesare Franchini, Michele Reticcioli, Martin Setvin, and Ulrike Diebold. Polarons in materials. Nature Reviews Materials 1-27 (2021).

link to publication

Literature discussed in the lecture & lecture notes will be available on moodle:

https://moodle.uni-jena.de/course/view.php?id=30409

Tentative program:

13.04.2022 - overview of the polaron topic

20.04.2022 - discussion of the paper by Lev Landau, titled "Electron motion in crystal lattices", Phys. Z. Sowjet. 3, 664 (1933), and derivation of the Landau-Pekar (LP) energy functional

27.04.2022 - derivation of the polaron equation of Landau and Pekar (LP)

04.05.2022 - Post-LP polaron theories; Hartree-Fock theory

11.05.2022 - Density-functional theory (DFT) - principles

18.05.2022 - discussion of the paper "Limitation of Fermi level shifts by polaron defect states in hematite photoelectrodes" by Christian Lohaus, Andreas Klein and Wolfram Jaegermann, Nature Communications 9, 4309 (2018)

25.05.2022 - DFT - implementation(s)

01.06.2022 - beyond DFT for modeling polarons

08.06.2022 - beyond DFT for modeling polarons; discussion of the paper “Direct view at excess electrons in TiO2 rutile and anatase” by Setvin, M. et al., Phys. Rev. Lett. 113, 086402 (2014)

15.06.2022 - discussion of the paper “Optical absorption induced by small polaron formation in transition metal oxides: The case of Co3O4” by Smart, T. J., Pham, T. A., Ping, Y. & Ogitsu, T., Phys. Rev. Mater. 3, 102401 (2019)

22.06.2022 - discussion of the paper “Semiconducting transition-metal oxides based on d5 cations: Theory for MnO and Fe2O3” by Haowei Peng and Stephan Lany, Phys. Rev. B 85, 201202(R) (2012)

29.06.2022 - student presentation of the paper “Niobium doped TiO2 : Intrinsic transparent metallic anatase versus highly resistive rutile phase” by Zhang, S. X. et al., J. Appl. Phys. 102, 013701 (2007)

06.07.2022 - ab initio polaron equations - Sio et al., "Ab initio theory of polarons: Formalism and applications", Phys. Rev. B 99, 235139 (2019); Sio et al., "Polarons from first principles without supercells", PRL 122, 246403 (2019)

(13.07.2022 - ab initio polaron equations continued)

Prior knowledge required:
basic QM, basic solid state physics (Schrödinger equation, concept of electronic band structure, phonons)

presentation about a subtopic or oral exam

Polarons, or charge carriers coupled to crystal lattice deformations, are a very common phenomenon in crystalline materials.
They can determine electrical conductivity and are even capable of inducing metal-semiconductor transitions.
This lecture will give an overview of historical theoretical treatment of polarons and then focus on more recent ab initio modeling of polarons.