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arXiv · 1007.2632

Critical Excitation Spectrum of Quantum Chain With A Local 3-Spin Coupling

John F. McCabe·Tomasz Wydro
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Abstract

This article reports a measurement of the low-energy excitation spectrum along the critical line for a quantum spin chain having a local interaction between three Ising spins and longitudinal and transverse magnetic fields. The measured excitation spectrum agrees with that predicted by the (D$_4$, A$_4$) conformal minimal model under a nontrivial correspondence between translations at the critical line and discrete lattice translations. Under this correspondence, the measurements confirm a prediction that the critical line of this quantum spin chain and the critical point of the 2D 3-state Potts model are in the same universality class.

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BibTeXRIS

John F. McCabe, Tomasz Wydro. 2010-07-15. Critical Excitation Spectrum of Quantum Chain With A Local 3-Spin Coupling. https://doi.org/10.1103/physreve.84.031123

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