Abstract

We demonstrate the realization of a Kondo insulator phase in a moiré superlattice of monolayer WS₂ / bilayer WSe2. The structure hosts moiré flat bands in the WSe₂ layer interfacing WS₂ and dispersive bands in the other WSe₂ layer. When both WSe₂ layers are partially doped but with a total density of two holes per moiré unit cell, an insulating state appears when the density of the moiré band is below one hole per moiré unit cell. The insulating state disappears above a threshold magnetic field and the system becomes metallic, indicating a Kondo insulator. The physics is explained by a periodic Anderson lattice model including on-site Coulomb repulsion in the moiré flat band and hybridization between moiré flat and non-moiré dispersive bands.

Abstract

We demonstrate the realization of a Kondo insulator phase in a moiré superlattice of monolayer WS₂ / bilayer WSe2. The structure hosts moiré flat bands in the WSe₂ layer interfacing WS₂ and dispersive bands in the other WSe₂ layer. When both WSe₂ layers are partially doped but with a total density of two holes per moiré unit cell, an insulating state appears when the density of the moiré band is below one hole per moiré unit cell. The insulating state disappears above a threshold magnetic field and the system becomes metallic, indicating a Kondo insulator. The physics is explained by a periodic Anderson lattice model including on-site Coulomb repulsion in the moiré flat band and hybridization between moiré flat and non-moiré dispersive bands.

Abstract

We demonstrate the realization of a Kondo insulator phase in a moiré superlattice of monolayer WS₂ / bilayer WSe2. The structure hosts moiré flat bands in the WSe₂ layer interfacing WS₂ and dispersive bands in the other WSe₂ layer. When both WSe₂ layers are partially doped but with a total density of two holes per moiré unit cell, an insulating state appears when the density of the moiré band is below one hole per moiré unit cell. The insulating state disappears above a threshold magnetic field and the system becomes metallic, indicating a Kondo insulator. The physics is explained by a periodic Anderson lattice model including on-site Coulomb repulsion in the moiré flat band and hybridization between moiré flat and non-moiré dispersive bands.

Abstract

We demonstrate the realization of a Kondo insulator phase in a moiré superlattice of monolayer WS₂ / bilayer WSe2. The structure hosts moiré flat bands in the WSe₂ layer interfacing WS₂ and dispersive bands in the other WSe₂ layer. When both WSe₂ layers are partially doped but with a total density of two holes per moiré unit cell, an insulating state appears when the density of the moiré band is below one hole per moiré unit cell. The insulating state disappears above a threshold magnetic field and the system becomes metallic, indicating a Kondo insulator. The physics is explained by a periodic Anderson lattice model including on-site Coulomb repulsion in the moiré flat band and hybridization between moiré flat and non-moiré dispersive bands.