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arXiv · 1011.2603

Spin operator matrix elements in the quantum Ising chain: fermion approach

N. Iorgov·V. Shadura·Yu. Tykhyy
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Abstract

Using some modification of the standard fermion technique we derive factorized formula for spin operator matrix elements (form-factors) between general eigenstates of the Hamiltonian of quantum Ising chain in a transverse field of finite length. The derivation is based on the approach recently used to derive factorized formula for Z_N-spin operator matrix elements between ground eigenstates of the Hamiltonian of the Z_N-symmetric superintegrable chiral Potts quantum chain. The obtained factorized formulas for the matrix elements of Ising chain coincide with the corresponding expressions obtained by the Separation of Variables Method.

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N. Iorgov, V. Shadura, Yu. Tykhyy. 2010-11-11. Spin operator matrix elements in the quantum Ising chain: fermion approach. https://doi.org/10.1088/1742-5468%2F2011%2F02%2Fp02028

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