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arXiv:cond-mat/0306285 · Journal of Physics A Mathematical and General

Out of equilibrium correlation functions of quantum anisotropicXYmodels: one-particle excitations

Luigi Amico A, Andreas Osterloh

Published Dec 15, 2003• 22 citations
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Abstract

We calculate exactly matrix elements between non-equilibrium excitations of the quantum XY model for general anisotropy. These matrix elements are expressed as a sum of Pfaffians. For single particle excitations on the ground state, the Pfaffians in the sum simplify to determinants.
DOI
10.1088/0305-4470/37/2/001

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