一个横向场的伊辛磁铁中的量子关键波动
A Hauspurg1,2, K Matsuura3, Taka-Hisa Arima3
1Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf (HZDR), 01328 Dresden, Germany.
概括
量子关键波动影响旋转-1/2 一维的伊辛磁体. 在酸 (CoNb2O6) 中的超声波测量揭示了与量子临界点相关的异常,为预测磁顺序相图提供了证据.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 磁力学和磁性材料的使用
- 量子关键的现象 量子关键的现象
背景情况:
- 酸 (CoNb2O6) 作为一个模型系统,用于研究旋转-1/2 一维 (1D) 横向场的Ising磁铁 (TFIM).
- 这种材料具有低的三维 (3D) Néel 排序温度 (TN = 2.95 K),使其适用于低温调查.
- 了解1D量子关键性和3D排序之间的相互作用对于磁性系统至关重要.
研究的目的:
- 通过超声波测量,研究CoNb2O6在沿b方向应用的横向磁场下的行为.
- 识别和描述与磁性排序和量子关键波动相关的声学模式中的异常.
- 为TFIM预测的通用相图提供实验证据,并叠加3D排序.
主要方法:
- 在低至0.3K的温度下对CoNb2O6样本进行了超声波测量.
- 横向磁场沿b方向应用,以探测磁相过渡.
- 横向声学模式c66被监测到异常,特别是软化,表明相位过渡和关键波动.
主要成果:
- 在进入3D有序状态时,在横向声学模式c66中观察到明显的异常.
- 在1.3K和1.5K之间,在4.7T左右检测到c66模式的几乎分歧的软化.
- 在磁场低于和高于4.7 T时,这种软化显著减少,这表明量子关键波动的影响.
结论:
- 观察到的声学异常被解释为源自1D Ising旋转链的量子临界点 (QCP) 的量子临界波动的影响.
- 该研究确定了1D链的QCP约为4.75T,低于3D订单的QCP约为5.4T.
- 这些发现提供了明确的实验证据,支持TFIM系统与叠加3D排序的预测通用相图.
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