Normal state pair nematicity and hidden magnetic order and metal-insulator (fermion-boson)- crossover origin of pseudogap phase of cuprates II

TL;DR

This paper explores the pseudogap phase in cuprates, focusing on nematicity, hidden magnetic order, and metal-insulator crossover phenomena, providing a unified understanding of various experimental observations and phase transitions.

Contribution

It offers a novel theoretical framework linking pseudogap phenomena, nematicity, and hidden magnetic order to PG pair physics, explaining diverse experimental results in cuprates.

Findings

Nematicity and hidden magnetic order relate to PG pair intra charge and spin fluctuations.

The paper explains the Fermi liquid oscillating ground state in YBCO versus insulating Bi-2212.

It predicts a specific temperature dependence of charge density near critical doping.

Abstract

In the present paper II, we will gain an understanding of the nematicity, insulating ground state (IGS), nematicity to stripe phase transition, Fermi pockets evolution, and resistivity temperature upturn, as to be metal - insulator (fermion-boson)- crossover (MIC) phenomena for the pseudogap (PG) region of cuprates. While in the paper I [1], we obtained an understanding of the observed heat conductivity downturn, anomalous Lorentz ratio, insulator resistivity boundary, nonlinear entropy as manifestations of the same MIC. The recently observed nematicity and hidden magnetic order are related to the PG pair intra charge and spin fluctuations. We will try to obtain an answer on the question: why ground state of YBCO is Fermi liquid oscillating and of Bi-2212 is insulating? We will also clarify the physics of the recently observed MIC results of Lalibert\'e et al. [2] and explain the long-discussed transition of the electric charge density from doping to doping+1 dependence at the critical doping. We predict that at the upturns this density should have the temperature dependence $n\sim T^3n_2$ for $T\rightarrow 0$, where $n_2$ is density for dopings close to the critical value. We understood that the upturns before and after the first critical doping have the same nature. We will find understanding of all above mentioned phenomena within the PG pair physics.