Tight-Binding Model for Spontaneous Magnetism of Quantum Dot Lattices
نویسندگان
چکیده
We use a simple tight-binding model to study the magnetism of twodimensional quantum dot lattices with 1 to 12 electrons per dot. The results show that in the middle of an electron shell the lattice favours antiferromagnetism while with nearly empty or full shells ferromagnetism is favoured. The size of the antiferromagnetic region increases with the coordination number of the dot. A one-dimensional dot lattice shows a spin-Peierls transition. The results for a square lattice are in good agreement with density functional calculations of Koskinen et al. [13].
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