Hole-Doping Effects on a Two-dimensional Kondo Insulator

TL;DR

This paper investigates how hole doping influences the properties of a two-dimensional Kondo insulator near a quantum critical point, revealing the gradual loss of quasiparticle states as the transition between phases occurs.

Contribution

It introduces a detailed analysis of hole doping effects on a 2D Kondo insulator near quantum criticality using advanced theoretical methods.

Findings

Quasiparticle states diminish near the quantum critical point.

Dynamical properties of doped holes are clarified in different phases.

Similarities and differences between spin liquid and magnetically ordered phases are discussed.

Abstract

We study the effects of hole doping on the two-dimensional Heisenberg-Kondo model around the quantum critical point, where the spin liquid phase (Kondo insulator) and the magnetically ordered phase are separated via a second-order phase transition. By means of the self-consistent Born approximation within the bond operator formalism as well as the standard spin wave theory, we discuss dynamical properties of a doped hole. It is clarified that a quasi-particle state stabilized in the spin liquid phase is gradually obscured as the system approaches the quantum critical point. This is also the case for the magnetically ordered phase. We argue the similarity and the difference between these two cases.