标题： 反铁磁性NiPS$_3$中的特征激子能量尺度 显示英文标题

标题： Characteristic exciton energy scales in antiferromagnetic NiPS$_3$

摘要： 二维反铁磁体是自旋电子学的有前景的材料。 由于具有与磁有序密切相关的超窄激子特性的范德瓦尔斯反铁磁体NiPS$_3$引起了广泛兴趣。 在这里，我们使用飞秒太赫兹光谱研究了NiPS$_3$中的光激发载流子。 我们确定了带间跃迁的起始点，并通过瞬态谱权重随激发波长和能量依赖关系估计了激子离化能。 我们的结果为量化NiPS$_3$的激子特性并验证其能带结构提供了关键见解。 显示英文摘要

摘要： Two-dimensional antiferromagnets are promising materials for spintronics. The van der Waals antiferromagnet NiPS$_3$ has attracted extensive interest due to its ultra-narrow exciton feature which is closely linked with the magnetic ordering. Here, we use time-resolved terahertz spectroscopy to investigate photo-excited carriers in NiPS$_3$. We identify the onset of interband transitions and estimate the exciton dissociation energy from the excitation wavelength and fluence dependence of the transient spectral weight. Our results provide key insights to quantify the exciton characteristics and validate the band structure for NiPS$_3$.