Thermodynamics and tunneling spectroscopy in the pseudogap regime of the boson fermion model

TL;DR

This paper explains the tunneling conductance asymmetry observed in STM experiments on Bi_2 Sr_2 CaCu_2 O_{8+x} using the boson fermion model, highlighting the pseudogap's particle-hole asymmetry and its dependence on boson concentration.

Contribution

It demonstrates that the boson fermion model can account for tunneling asymmetry and pseudogap features observed experimentally, providing a theoretical explanation for these phenomena.

Findings

Tunneling conductance asymmetry can be explained by the boson fermion model.

The pseudogap exhibits particle-hole asymmetry.

Asymmetry depends on boson concentration.

Abstract

Motivated by the STM experimental data on Bi_2 Sr_2 CaCU_2 O_{8+x} which indicate the tunneling conductance asymmetry sigma(-V) not equal sigma(V), we report that such a behavior can be explained in terms of the boson fermion model. It has been shown in the recent studies, based on various selfconsistent techniques to capture the many-body effects, that the low energy spectrum of the boson fermion model is featured by an appearance of the pseudogap at T^* > T_c. We argue that the pseudogap structure has to exhibit a particle-hole asymmetry. This asymmetry may eventually depend on the boson concentration.