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Application of the Interface Approach in Quantum Ising Models

Parongama Sen
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Abstract

We investigate phase transitions in the Ising model and the ANNNI model in transverse field using the interface approach. The exact result of the Ising chain in a transverse field is reproduced. We find that apart from the interfacial energy, there are two other response functions which show simple scaling behaviour. For the ANNNI model in a transverse field, the phase diagram can be fully studied in the region where a ferromagnetic to paramagnetic phase transition occurs. The other region can be studied partially; the boundary where the antiphase vanishes can be estimated.

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Parongama Sen. 1997-02-27. Application of the Interface Approach in Quantum Ising Models. https://doi.org/10.1103/physrevb.55.11367

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