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arXiv · 1111.3488

Application of Uniform Matrix Product State to Quantum Phase Transition with a Periodicity Change

Hiroshi Ueda·Isao Maruyama
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Abstract

As a method beyond the mean-field analysis, a matrix product state (MPS) with incommensurate periodicity is applied to detect phase transitions accompanied with periodicity change, where the incommensurate MPS is generated by acting local-spin-rotation operators with the incommensurate periodicity on a uniform MPS. As a commensurate/commensurate change, we calculate the partial ferro -- perfect ferro phase transition in the $S=1/2$ Heisenberg model and its critical exponent of the magnetization curve. As a commensurate/incommensurate change, we calculate the S=1 Heisenberg model with bilinear and biquadratic interactions which has periodicity change in the spin-spin correlation function.

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Hiroshi Ueda, Isao Maruyama. 2011-11-15. Application of Uniform Matrix Product State to Quantum Phase Transition with a Periodicity Change. https://doi.org/10.1143/jpsjs.81sb.sb065

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