Interacting holes in Si and Ge double quantum dots: From a multiband approach to an effective-spin picture

  title={Interacting holes in Si and Ge double quantum dots: From a multiband approach to an effective-spin picture},
  author={Andrea Secchi and Laura Bellentani and Andrea Bertoni and Filippo Troiani},
  journal={Physical Review B},
The states of two electrons in tunnel–coupled semiconductor quantum dots can be effectively described in terms of a two–spin Hamiltonian with an isotropic Heisenberg interaction. A similar description needs to be generalized in the case of holes due to their multiband character and spin– orbit coupling, which mixes orbital and spin degrees of freedom, and splits J = 3/2 and J = 1/2 multiplets. Here we investigate two–hole states in prototypical coupled Si and Ge quantum dots via different… 
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