You are cordially invited to the SCL seminar of the Center for the Study of Complex Systems, which will be held on Thursday, April 4 at 14:00 in the library reading room “Dr. Dragan Popović" of the Institute of Physics Belgrade. The talk entitled

Exploring Polarons in Semiconductors: Insights from the Holstein Model

will be given by Petar Mitrić, Institute of Physics Belgrade.

Abstract:

The electron-phonon interaction significantly affects the properties of semiconducting materials, leading to the emergence of polarons — a new quasiparticle that now, instead of the electron, plays the role of the current carrier in our system. The polarons are often studied using theoretically idealized models, the simplest of which is the Holstein model. In this talk, we show that within this model, the dynamical mean-field theory can be used to obtain almost numerically exact results for both the quasiparticle and single-particle properties, regardless of the electron-phonon coupling strength, phonon frequency, or temperature [1]. Surprisingly, this remains true regardless of the dimensionality of our system. Furthermore, we use these results as a benchmark to test the reliability of the increasingly popular cumulant expansion method for the calculation of various quantities in a wide range of regimes [2]. At the end, we examine the transport properties within the Holstein model which was our original motivation at the start of this study.

[1] P. Mitrić, V. Janković, N. Vukmirović, and D. Tanasković, Phys. Rev. Lett., 129, 096401 (2022).
[2] P. Mitrić, V. Janković, N. Vukmirović, and D. Tanasković, Phys. Rev. B, 107, 125165 (2023).