Ferromagnetism in the Extended Periodic Anderson Model Near Selective Mott Localization

TL;DR

This paper rigorously demonstrates the emergence of ferromagnetic metallic phases near selective Mott localization in an extended periodic Anderson model, linking theoretical insights with experimental observations in materials like UGe2.

Contribution

It provides a rigorous proof of ferromagnetic metallic phases in higher dimensions within the extended periodic Anderson model, connecting flat-band ferromagnetism and double exchange mechanisms.

Findings

Ferromagnetic metallic phase found near selective Mott localization.

Connections established between flat-band ferromagnetism and double exchange.

Relevance to experimental ferromagnetism in UGe2.

Abstract

Motivated by the experimental finding of Ferromagnetism (FM) near non-FL quantum phase transitions (QPT), I investigate FM in an Extended Periodic Anderson Model (EPAM). Using the Frobenius-Perron theorem, a FM {\it metallic} phase near the selective Mott localization is rigorously found. Interesting connections with Tasaki's flat-band ferromagnetism, as well as with the well-known double exchange (DE) mechanism are elucidated. This finding is a higher dimensional generalization of numerical work on the D=1 PAM, and constitutes a robust way to FM metallic behavior in $D>1$. Finally, we discuss a concrete manifestation of our results to $UGe_{2}$.