Regular Article

Superconductivity and intra-unit-cell electronic nematic phase in the three-band model of cuprates

¹ Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow, Poland
² Institute of Theoretical Physics, Jagiellonian University, ul. Łojasiewicza 11, 30-348 Krakow, Poland

^a e-mail: michal.zegrodnik@agh.edu.pl

Received: 8 June 2020
Accepted: 17 August 2020
Published online: 21 September 2020

Abstract

The intra-unit-cell nematic phase is studied within the three-band Emery model of the cuprates by using the diagrammatic expansion of the Gutzwiller wave function (DE-GWF). According to our analysis a spontaneous rotational (C₄) symmetry breaking of the electronic wave function, leading to the nematic behavior, can appear due to electron correlations induced mainly by the onsite Coulomb repulsion, even in the absence of the corresponding intersite oxygen–oxygen repulsion term. The latter has been considered as the triggering factor of the nematic state formation in a number of previous studies. Also, we show that at the transition to the nematic phase, electron concentration transfer from d- to p-orbitals takes place, apart from the usually discussed p_x∕p_y polarization. The nematicity appears in a similar doping range as the paired phase, showing that both phases may have a common origin, even though they compete. As we show a coexistence region of both superconductivity and nematicity appears in a relatively wide doping range. The results are discussed in view of the experimental findings corresponding to the relation between nematicity and pseudogap behavior.