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Spectrum and correlation functions of a quasi-one-dimensional quantum Ising model

Sam T. Carr·Alexei M. Tsvelik
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Abstract

We consider a model of weakly coupled quantum Ising chains. We describe the phase diagram of such a model and study the dynamical magnetic susceptibility by means of Bethe ansatz and the Random Phase Approximation applied to the inter-chain exchange. We argue that some of the beautiful physics of the quantum Ising chain in a magnetic field survives in the ordered state of the quasi-one-dimensional model and can be observed experimentally by means of neutron scattering.

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Sam T. Carr, Alexei M. Tsvelik. 2003-03-25. Spectrum and correlation functions of a quasi-one-dimensional quantum Ising model. https://doi.org/10.1103/physrevlett.90.177206

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