标题： Co_8Zn_7Mn\_5 和 Co_8Zn_8Mn_4 中的非传统弛豫动力学：惯性效应的证据 显示英文标题

标题： Unconventional Relaxation Dynamics in Co_8Zn_7Mn_5 and Co_8Zn_8Mn_4: Evidence of Inertial Effects

摘要： 磁化弛豫动力学是揭示控制磁性系统磁响应和能量耗散内在机制的重要工具。 在这项工作中，我们研究了Beta Mn型Co_8Zn_7Mn_5和Co_8Zn_8Mn_4在1 kHz到10 kHz频率范围内的弛豫动力学，涵盖了不同的磁相。 虽然大多数磁性系统倾向于遵循具有非零分布的Debye型弛豫或Cole-Cole形式主义，但我们的分析显示，这些常规模型无法捕捉Co_8Zn_7Mn_5和Co_8Zn_8Mn\_4在不同磁相中的交流磁化率的频率依赖性。 相反，需要一个惯性成分来成功描述这些动力学，这表明存在非常规的弛豫行为。 对于这两种组成，特征弛豫时间被发现为10^-5秒量级。 弛豫时间随磁场的变化表现出非单调特性，在斯格明子相变时呈现出双峰结构，表明在相边界处弛豫动力学较慢。 此外，纯相中等温磁化率与绝热磁化率之间的非零差异的存在意味着弛豫动力学较慢，这与纯相中存在有限耗散一致。 惯性项之前已被用来描述由于磁单极传播而在自旋冰系统中的动力学。 然而，在这个系统中需要它，表明磁化动力学的更广泛意义超出了传统的自旋冰和斯格明子。 显示英文摘要

摘要： Magnetization relaxation dynamics serve as an essential tool for uncovering the intrinsic mechanisms governing the magnetic response and energy dissipation in magnetic systems. In this work, we examine the relaxation dynamics for Beta Mn type Co_8Zn_7Mn_5 and Co_8Zn_8Mn_4 across a frequency range of 1 kHz to 10 kHz, spanning different magnetic phases. While most magnetic systems tend to follow the Debye-like relaxation with non-zero distribution or the Cole-Cole formalism, our analysis reveal that these conventional models fail to capture frequency dependence of ac susceptibility across different magnetic phases in Co_8Zn_7Mn_5 and Co_8Zn_8Mn_4. Instead, an inertial component is needed to successfully describe the dynamics, suggesting the presence of unconventional relaxation behavior. The characteristic relaxation time is found to be of the order of 10^-5 s for both the compositions. The field dependent variation of relaxation time exhibits a non-monotonic nature, with the double peak like structure at the skyrmion phase transitions, implying slower relaxation dynamics at the phase boundaries. Furthermore, the presence of non-zero difference between isothermal and adiabatic susceptibility in the pure phases implies slower relaxation dynamics, which is consistent with the presence of finite dissipation in pure phases. The inertial term has been previously invoked to describe the dynamics in spin ice systems due to the propagation of magnetic monopoles. However, its necessity in this system, points to a wider significance in magnetization dynamics that goes beyond the conventional spin ices and skyrmions.