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arXiv 0903.3785cond-mat.str-el
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广义Kitaev模型中的禁闭-解除禁闭相变

Confinement-deconfinement transition in a generalized Kitaev model

S. Mandal, S. Bhattacharjee, K. Sengupta, R. Shankar

摘要:

我们提出了一个自旋模型,即,Kitaev模型增加了一个循环项和扰动的伊辛哈密顿量,并表明它既表现出限制-解除限制从自旋液体反铁磁/自旋链/铁磁相和拓扑量子相变之间的带隙和无隙自旋液相。我们发展了一个费米子平均场论来绘制模型的相图,并估计了其自旋液相的稳定性,这可能与在光晶格中实现模型的尝试有关。我们还推测,在模型中的一些约束解除禁闭过渡,预测为一阶内的平均场论,可能会成为二阶通过缺陷凝聚机制。

英文摘要:

We present a spin model, namely, the Kitaev model augmented by a loop term and perturbed by an Ising Hamiltonian and show that it exhibits both confinement-deconfinement transitions from spin liquid to antiferromagnetic/spin-chain/ferromagnetic phases and topological quantum phase transitions between gapped and gapless spin liquid phases. We develop a Fermionic mean-field theory to chart out the phase diagram of the model and estimate the stability of its spin liquid phases which might be relevant for attempts to realize the model in optical lattices. We also conjecture that some of the confinement-deconfinement transitions in the model, predicted to be first order within the mean-field theory, may become second order via a defect condensation mechanism.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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