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Chiral Kondo lattice in doped MoTe₂/WSe₂ bilayers.

ABSTRACT: We theoretically study the interplay between magnetism and a heavy Fermi liquid in the AB-stacked transition metal dichalcogenide bilayer system, MoTe₂/WSe₂, in the regime in which the Mo layer supports localized magnetic moments coupled by interlayer electron tunneling to a weakly correlated band of itinerant electrons in the W layer. We show that the interlayer electron transfer leads to a chiral Kondo exchange, with consequences including a strong dependence of the Kondo temperature on carrier concentration and anomalous Hall effect due to a topological hybridization gap. The theoretical model exhibits two phases, a small Fermi surface magnet and a large Fermi surface heavy Fermi liquid; at the mean-field level, the transition between them is first order. Our results provide concrete experimental predictions for ongoing experiments on MoTe₂/WSe₂ bilayer heterostructures and introduces a controlled route to observe a topological selective Mott transition.

SUBMITTER: Guerci D

PROVIDER: S-EPMC10022889 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Chiral Kondo lattice in doped MoTe2/WSe2 bilayers.

Guerci Daniele D Wang Jie J Zang Jiawei J Cano Jennifer J Pixley J H JH Millis Andrew A

Science advances 20230317 11

We theoretically study the interplay between magnetism and a heavy Fermi liquid in the AB-stacked transition metal dichalcogenide bilayer system, MoTe2/WSe2, in the regime in which the Mo layer supports localized magnetic moments coupled by interlayer electron tunneling to a weakly correlated band of itinerant electrons in the W layer. We show that the interlayer electron transfer leads to a chiral Kondo exchange, with consequences including a strong dependenc ...[more]

PMID: 36930704

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