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Quantum Phase Transitions in the One-Dimensional S=1 Spin-Orbital Model: Implications for Cubic Vanadates

Satoshi Miyashita·Akira Kawaguchi·Norio Kawakami·Giniyat Khaliullin
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Abstract

We investigate ground-state properties and quantum phase transitions in the one-dimensional S=1 spin-orbital model relevant to cubic vanadates. Using the density matrix renormalization group, we compute the ground-state energy, the magnetization and the correlation functions for different values of the Hund's coupling $J_H$ and the external magnetic field. It is found that the magnetization jumps at a certain critical field, which is a hallmark of the field-induced first-order phase transition. The phase transition driven by $J_H$ is also of first order. We also consider how the lattice-induced ferro-type interaction between orbitals modifies the phase diagram, and discuss the results in a context of the first-order phase transition observed in YVO$_3$ at 77K.

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Satoshi Miyashita, Akira Kawaguchi, Norio Kawakami, Giniyat Khaliullin. 2003-10-09. Quantum Phase Transitions in the One-Dimensional S=1 Spin-Orbital Model: Implications for Cubic Vanadates. https://doi.org/10.1103/physrevb.69.104425

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