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Effects of a magnetic field on the one-dimensional spin-orbital model

Yu-Li Lee·Yu-Wen Lee
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Abstract

We study the effects of a uniform magnetic field on the one-dimensional spin-orbital model in terms of effective field theories. Two regions are examined: one around the SU(4) point (J=K/4) and the other with K< K/4, the excitation spectrum has a gap. When the magnetic field is beyond some critical value, a quantum phase transition occurs. However, the correlation functions around the SU(4) point and the region with K<<J exhibit distinct behavior. This results from different structures of excitation spectra in both regime.

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Yu-Li Lee, Yu-Wen Lee. 1999-10-20. Effects of a magnetic field on the one-dimensional spin-orbital model. https://doi.org/10.1103/physrevb.61.6765

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