Charge transfer spin-polarons and ferromagnetism in weakly doped AB-stacked TMD heterobilayers

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Guerci, Daniele, Pixley, J. H., Millis, Andrew J.
Formato: Preprint
Publicado: 2024
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866913575256195072
author Guerci, Daniele
Pixley, J. H.
Millis, Andrew J.
author_facet Guerci, Daniele
Pixley, J. H.
Millis, Andrew J.
contents We study the formation of ferromagnetic and magnetic polaron states in weakly doped heterobilayer transition metal dichalcogenides in the ``heavy fermion'' limit in which one layer hosts a dense set of local moments and the other hosts a low density of itinerant holes. We show that interactions among the carriers in the itinerant layer induces a ferromagnetic exchange. We characterize the ground state finding a competition, controlled by the carrier concentration and interlayer exchange, between a layer decoupled phase of itinerant carriers in a background of local moments, a fully polarized ferromagnet and a canted antiferromagnet. In the canted antiferromagnet phase the combination of the in-plane 120$^{\circ}$ Néel order and Ising spin orbit couplings induces winding in the electronic wavefunction giving rise to a topologically non-trivial spin texture and an observable anomalous Hall effect. At larger carrier density the ferromagnetically ordered phase transitions into a paramagnetic heavy Fermi liquid state. This theory enables a comprehensive understanding of the existing experimental observations while also making predictions including experimental signatures enabling direct imaging of spin polaron bound states with scanning tunneling microscopy. Our work shows that the prevailing paradigm of the (Doniach) phase diagram of heavy fermion metals is fundamentally modified in the low doping regime of heterobilayer transition metal dichalcogenides.
format Preprint
id arxiv_https___arxiv_org_abs_2411_05908
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Charge transfer spin-polarons and ferromagnetism in weakly doped AB-stacked TMD heterobilayers
Guerci, Daniele
Pixley, J. H.
Millis, Andrew J.
Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
We study the formation of ferromagnetic and magnetic polaron states in weakly doped heterobilayer transition metal dichalcogenides in the ``heavy fermion'' limit in which one layer hosts a dense set of local moments and the other hosts a low density of itinerant holes. We show that interactions among the carriers in the itinerant layer induces a ferromagnetic exchange. We characterize the ground state finding a competition, controlled by the carrier concentration and interlayer exchange, between a layer decoupled phase of itinerant carriers in a background of local moments, a fully polarized ferromagnet and a canted antiferromagnet. In the canted antiferromagnet phase the combination of the in-plane 120$^{\circ}$ Néel order and Ising spin orbit couplings induces winding in the electronic wavefunction giving rise to a topologically non-trivial spin texture and an observable anomalous Hall effect. At larger carrier density the ferromagnetically ordered phase transitions into a paramagnetic heavy Fermi liquid state. This theory enables a comprehensive understanding of the existing experimental observations while also making predictions including experimental signatures enabling direct imaging of spin polaron bound states with scanning tunneling microscopy. Our work shows that the prevailing paradigm of the (Doniach) phase diagram of heavy fermion metals is fundamentally modified in the low doping regime of heterobilayer transition metal dichalcogenides.
title Charge transfer spin-polarons and ferromagnetism in weakly doped AB-stacked TMD heterobilayers
topic Strongly Correlated Electrons
Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2411.05908