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Expansions for one quasiparticle states in spin 1/2 systems

Nilanjana Datta·Tom Kennedy
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Abstract

Convergent expansions of the wavefunctions for the ground state and low-lying excited states of quantum transverse Ising systems are obtained. These expansions are employed to prove that the dispersion relation for a single quasi-particle has a convergent expansion.

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Nilanjana Datta, Tom Kennedy. 2003-01-17. Expansions for one quasiparticle states in spin 1/2 systems. https://arxiv.org/abs/cond-mat/0104199

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