Impurity scattering and Friedel oscillations in model correlated fermionic systems

*Banhi Chatterjee
Institute of Physics, Czech Academy of Sciences, Prague, Czech Republic

Scattering from the impurities and the resulting Friedel oscillations (FO) in the Fermi liquid phase, Mott insulating phase, and at the Mott transition is studied in finite lattice systems using the one-band Hubbard model, both at zero and finite temperatures in the presence of a single impurity potential [1,2,3]. The problem is also extended for the cases of multiple impurities. These impurities model the effects of defects and adsorbed atoms on the surfaces of real systems with correlated electrons. Electronic correlations are accounted for by solving the real-space dynamical mean-field theory (R-DMFT) equations, and also using other reliable yet computationally cheap self-energy approximations based on the R-DMFT. It is seen that the FO is damped with the interaction and the Fermi liquid renormalization factor is primarily responsible for this damping. FO almost disappears at the Mott transition and completely beyond it in the Mott insulating phase. The screening charge decreases with the interactions and approaches zero towards the Mott transition. It is left as an open question if any signatures of FO can be observed in real Mott systems, e.g. transition metal oxides which are the potential functional materials for the Mott transistors [4,5]. Moreover, it is interesting to probe if these quantum oscillations would affect the different transport properties, e.g. transport current, resistivity etc. in such systems.

[1] B. Chatterjee, J. Skolimowski, K. Makuch, K. Byczuk, arXiv:1807.08566 (under review)

[2] B. Chatterjee, K. Byczuk, JPCS 592, 012059 (2015).

[3] K. Byczuk, B. Chatterjee, D. Vollhardt, Eur. Phys. J. B 92, 23 (2019).

[4] P. Maier, F. Hartmann et. al, App. Phys. Lett. 110, 093506 (2017).

[5] P. Scheiderer, M. Schmitt, Adv. Mat. 30, 25 (2018).