论文标题
正方形和四极人造自旋冰的磁场依赖性热力学特性
Magnetic-Field-Dependent Thermodynamic Properties of Square and Quadrupolar Artificial Spin Ice
论文作者
论文摘要
应用的磁场是人造自旋冰（ASI）系统的重要调谐参数，因为它们可以在不同的磁接地态之间驱动相变，或者通过具有较高的新兴磁激发（例如，单极样的quasiparticles）进行调整。在这里，使用实验支持的模拟，我们研究了正方形和四极ASI的热力学特性和磁性阶段，这是施加的平面磁场的函数。蒙特卡洛模拟用于在平衡条件下生成磁化，磁性热，热力学磁化波动和磁性参数的磁化图。这些地图揭示了磁性有序的多样性以及在这些ASIS的相图的不同区域发生的相变，并且通过热活动ASIS中平衡“磁化噪声”的磁光测量值在实验上支持。
Applied magnetic fields are an important tuning parameter for artificial spin ice (ASI) systems, as they can drive phase transitions between different magnetic ground states, or tune through regimes with high populations of emergent magnetic excitations (e.g., monopole-like quasiparticles). Here, using simulations supported by experiments, we investigate the thermodynamic properties and magnetic phases of square and quadrupolar ASI as a function of applied in-plane magnetic fields. Monte Carlo simulations are used to generate field-dependent maps of the magnetization, the magnetic specific heat, the thermodynamic magnetization fluctuations, and the magnetic order parameters, all under equilibrium conditions. These maps reveal the diversity of magnetic orderings and the phase transitions that occur in different regions of the phase diagrams of these ASIs, and are experimentally supported by magneto-optical measurements of the equilibrium "magnetization noise" in thermally-active ASIs.
