Doped Spin Ladder: Zhang-Rice Singlets or Rung-centred Holes?
نویسنده
چکیده
We formulate charge transfer model for a single doped spin ladder, relevant for the intrinsically doped plane of coupled spin ladders in Sr3Ca11Cu24O41. Assuming the presence of the experimentally observed charge order in the system we solve the model using Hartree-Fock approximation. Our results show the profound stability of the Zhang-Rice singlets with respect to other configurations of doped holes, in agreement with recent x-ray absorption measurements.
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