AI 中文总结
本研究利用THz-TDS技术，提出磁导率与介电常数解耦的提取方法，在层状NiPS₃中观测到磁振子模式与区折叠声子，成功建模磁导率并提取自旋动力学参数。
AI 中文摘要
三硫化三镍磷（NiPS₃）是一种具有XY型反铁磁有序的莫特绝缘体，备受关注。本研究采用太赫兹时域光谱（THz-TDS）技术，作为温度的函数，研究单晶NiPS₃的电动力学响应。当磁导率不能近似为1时，传统太赫兹透射分析通常局限于复折射率，阻碍了磁贡献与介电贡献的区分。为克服这一局限，本文展示了一种能够将磁导率与介电常数解耦的提取方法。假设介电贡献在奈尔温度（TN）以下保持不变，我们使用顺磁相的数据分离出13 K下的本征磁分量。光谱的角向和热依赖性揭示了1 THz附近（0°取向）的一个磁振子模式，以及由对称性破缺激活的、独特的区折叠声子（90°取向）。分离出的磁导率已成功用德鲁德-洛伦兹振子建模，从而提取出该材料的基本自旋动力学参数。
英文摘要
Nickel phosphorus trisulfide (NiPS$_3$) stands out as a Mott insulator exhibiting XY-type antiferromagnetic order. In this work, we investigate the electrodynamic response of single-crystalline NiPS$_3$ using Terahertz Time-Domain Spectroscopy (THz-TDS) as a function of temperature. In cases where the magnetic permeability cannot be approximated to unity, conventional THz transmission analysis is often restricted to the complex refractive index, hindering the distinction between magnetic and dielectric contributions. To overcome this limitation, we demonstrate an extraction methodology capable of decoupling the magnetic permeability from the electric permittivity. Assuming that the dielectric contribution remains invariant below the N'eel temperature (TN), we used data from the paramagnetic phase to isolate the intrinsic magnetic component at 13 K. The angular and thermal dependence of the spectra revealed a magnon mode near 1 THz (for 0$^\circ$ orientation) and, distinctively, a zone-folded phonon activated by symmetry breaking (at 90$^\circ$). The isolated magnetic permeability was successfully modeled using Drude-Lorentz oscillators, enabling the extraction of fundamental spin dynamics parameters in this material.
Comments19 pages, 4 figures
