Analytic method for quadratic polarons in nonparabolic bands

Author(s)
S. N. Klimin, J. Tempere, M. Houtput, S. Ragni, T. Hahn, C. Franchini, A. S. Mishchenko
Abstract

Including the effect of lattice anharmonicity on electron-phonon interactions has recently garnered attention due to its role as a necessary and significant component in explaining various phenomena, including superconductivity, optical response, and temperature dependence of mobility. This study focuses on analytically treating the effects of anharmonic electron-phonon coupling on the polaron self-energy, combined with numerical Diagrammatic Monte Carlo (DiagMC) data. Specifically, we incorporate a quadratic interaction into the method of squeezed phonon states, which has proven effective for analytically calculating the polaron parameters. Additionally, we extend this method to nonparabolic finite-width conduction bands while maintaining the periodic translation symmetry of the system. Our results are compared with those obtained from Diagrammatic Monte Carlo, partially reported in a recent study [S. Ragni, Phys. Rev. B 107, L121109 (2023)2469-995010.1103/PhysRevB.107.L121109], covering a wide range of coupling strengths for the nonlinear interaction. Remarkably, our analytic method predicts the same features as the Diagrammatic Monte Carlo simulation.

Organisation(s)
Computational Materials Physics
External organisation(s)
University of Antwerp, Harvard University, University of Bologna, Ulmer Fundamental Symmetries Laboratory, INSTITUT ZA FIZIKU, Flatiron Institute
Journal
Physical Review B
Volume
110
No. of pages
13
ISSN
2469-9950
DOI
https://doi.org/10.48550/arXiv.2403.18019
Publication date
08-2024
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics, 103015 Condensed matter, 103043 Computational physics
ASJC Scopus subject areas
Electronic, Optical and Magnetic Materials, Condensed Matter Physics
Portal url
https://ucrisportal.univie.ac.at/en/publications/56ab983a-7e57-4b0e-b1be-bff824ae5fe4