Many-body large polaron optical conductivity in SrTi_1-xNb_xO₃

2010/03/04 by J. T. Devreese, S. N. Klimin, J. L. M. van Mechelen +1 · 1 citation
Physics and Astronomy · #cond-mat.str-el #cond-mat.mtrl-sci

paper · pdf · doi:10.1103/physrevb.81.125119

published as Phys. Rev. B 81, 125119 (2010) · to appear in Phys. Rev. B

arxiv created 2010/03/04 · arxiv updated 2015/05/18

Abstract

Recent experimental data on the optical conductivity of niobium doped SrTiO₃ are interpreted in terms of a gas of large polarons with effective coupling constant α_eff≈2. The theoretical approach takes into account many-body effects, the electron-phonon interaction with multiple LO-phonon branches, and the degeneracy and the anisotropy of the Ti t_2g conduction band. Based on the Fröhlich interaction, the many-body large-polaron theory provides an interpretation for the essential characteristics, except -- interestingly -- for the unexpectedly large intensity of a peak at ∼130 meV, of the observed optical conductivity spectra of SrTi_1-xNb_xO₃ without any adjustment of material parameters.

Cited by

• Two-phonon pairing and superconductivity in SrTiO₃

Related

• Optical response of an interacting polaron gas in strongly polar crystals
• Polaronic behavior in a weak coupling superconductor
• Origin of unexpected large Seebeck effect in SrTiO3: nonperturbative polaron study from ab initio cumulant expansion
• Optical properties of an interacting large polaron gas
• Anharmonic multiphonon origin of the valence plasmon in SrTi1-xNbxO3