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arXiv · 1010.5773

High--order connected moments expansion for the Rabi Hamiltonian

Paolo Amore·Francisco M. Fernández·Martin Rodriguez
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Abstract

We analyze the convergence properties of the connected moments expansion (CMX) for the Rabi Hamiltonian. To this end we calculate the moments and connected moments of the Hamiltonian operator to a sufficiently large order. Our large--order results suggest that the CMX is not reliable for most practical purposes because the expansion exhibits considerable oscillations.

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Paolo Amore, Francisco M. Fernández, Martin Rodriguez. 2010-10-27. High--order connected moments expansion for the Rabi Hamiltonian. https://doi.org/10.2478/s11534-011-0101-9

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