Compressible Ferrimagnetism in the depleted Periodic Anderson Model

TL;DR

This study uses quantum Monte Carlo simulations to explore magnetic phases in a depleted periodic Anderson model, revealing ferrimagnetism and insulating behavior with finite compressibility, advancing understanding of correlated electron systems.

Contribution

It provides the first detailed quantum Monte Carlo analysis of magnetic order and conductivity in a depleted periodic Anderson model, highlighting compressible ferrimagnetism.

Findings

Enhanced antiferromagnetic correlations with single depletion

Ferrimagnetic ground state at half depletion of f-orbitals

Insulating behavior with finite compressibility at half-filling

Abstract

Tight-binding Hamiltonians with single and multiple orbitals exhibit an intriguing array of magnetic phase transitions. In most cases the spin ordered phases are insulating, while the disordered phases may be either metallic or insulating. In this paper we report a Determinant Quantum Monte Carlo study of interacting electrons in a geometry which can be regarded as a two-dimensional Periodic Anderson Model with depleted interacting ($f$) orbitals. For a single depletion, we observe an enhancement of antiferromagnetic correlations and formation of localized states. For half of the $f$-orbitals regularly depleted, the system exhibits a ferrimagnetic ground state. We obtain a quantitative determination of the nature of magnetic order, which we discuss in the context of Tsunetsugu's theorem, and show that, although the dc conductivity indicates insulating behavior at half-filling, the compressibility remains finite.