Configuration interaction in delta-doped heterostructures

We analyze the tunnel coupling between an impurity state located in a $\delta$-layer and the 2D delocalized states in the quantum well (QW) located at a few nanometers from the $\delta$ -- layer. The problem is formulated in terms of Anderson-Fano model as configuration interaction between the carrier bound state at the impurity and the continuum of delocalized states in the QW. An effect of this interaction on the interband optical transitions in the QW is analyzed. The results are discussed regarding the series of experiments on the GaAs structures with a $\delta$-Mn layer.Comment: arXiv admin note: substantial text overlap with arXiv:1111.089

Possible Wigner states in CrI3 heterostructures with graphene:A tight-binding model perspective

In this study, we present an effective tight-binding model for an accurate description of the lowest energy quadruplet of a conduction band in a ferromagnetic Cr⁢3 monolayer, tuned to the complementary ab initio density functional theory simulations. This model, based on a minimum number of chromium orbitals, captures a distinctively flat dispersion in those bands but requires taking into account hoppings beyond nearest neighbors, revealing ligand-mediated electron pathways connecting remote chromium sites. Doping of states in the lowest conduction band of Cr⁢3 requires charge transfer, which, according to recent studies [Tenasini et al., Nano Lett. 22, 6760 (2022); Tseng et al., Nano Lett. 22, 8495 (2022); Cardoso et al., Phys. Rev. B 108, 184423 (2023)], can occur in graphene⁡(G)/Cr⁢3 heterostructures. Here, we use the detailed description of the lowest conduction band in CrI3 to show that G/CrI3/G and G/CrI3 are type-II heterostructures where light holes in graphene would coexist with heavy electrons in the magnetic layer, where the latter can be characterized by Wigner-Seitz radius ∼25−35 (as estimated for hBN-encapsulated structures)