在一个旋转-1量子反铁磁体模型中的非界定伪批判性
Vikas Vijigiri1, Sumiran Pujari2, Nisheeta Desai3
1Department of Physics, Indian Institute of Technology Bombay, IIT Bombay, Powai, Mumbai 400 076, Maharashtra, India, Mumbai, 400076, INDIA.
概括
我们研究了一种自旋-1磁铁模型,发现磁相之间的过渡可能是伪临界的,而不是连续的. 这表明,在这种量子系统中,无限制的伪批判性更为常见.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子磁力 量子磁力 量子磁力
- 统计力学 统计力学
背景情况:
- 基于贝里相干扰的无界定量子关键性 (DQC) 理论解释了S=1/2反铁磁体中的连续过渡.
- 这一理论已经扩展到S=1磁体,提出连续的Néel到柱状价值键固体 (cVBS) 过渡.
研究的目的:
- 探索S=1磁体中连续过渡的显微模型.
- 在一个特定的正方形格子模型中,研究 Néel 到 cVBS 过渡的性质.
主要方法:
- 开发了一个方格格子模型,其中包含了海森伯格 (J H),二方格 (J B) 和 Q-term (Q B) 相互作用.
- 采用大型量子蒙特卡洛 (QMC) 模拟来分析模型的行为.
- 利用Binder分析和顺序参数直方图来描述关键现象.
主要成果:
- 对于J H = 0,该模型反映了SU(3) JQ模型,显示了类似DQC的Nel-cVBS过渡.
- 介绍J H (将对称性减少到SU(2)) 显示了暗示连续过渡的签名.
- 绑定器分析显示了次广泛的负差,表明伪批判性行为而不是真正的连续过渡.
结论:
- 在S=1模型中研究的Néel-cVBS过渡被解释为伪批判性.
- 无界限的伪批判性似乎比以前认为的更为普遍的场景,甚至在S=1系统中.
- 这些发现与最近对旋转-1/2模型的研究一致,加强了伪批判性的流行.
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