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Effective bosonic hamiltonian for excitons : a too naive concept

M. Combescot·O. Betbeder-Matibet
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Abstract

Excitons, being made of two fermions, may appear from far as bosons. Their close-to-boson character is however quite tricky to handle properly. Using our commutation technique especially designed to deal with interacting close-to-boson particles, we here calculate the exact expansion in Coulomb interaction of theexciton-exciton correlations, and show that a naive effective bosonic hamiltonian for excitons cannot produce these X-X correlations correctly.

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M. Combescot, O. Betbeder-Matibet. 2002-01-30. Effective bosonic hamiltonian for excitons : a too naive concept. https://doi.org/10.1209/epl%2Fi2002-00296-0

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