标题： 狄拉克磁体CoTiO3中的晶格诱导自旋动力学 显示英文标题

标题： Lattice-induced spin dynamics in Dirac magnet CoTiO3

摘要： 自旋-晶格耦合对于理解自旋电子学和磁子学应用中的自旋输运和动力学至关重要。最近，钴钛酸盐（CoTiO3）作为一种易平面反铁磁体，被发现具有大的磁矩的轴向声子，这可能源于自旋-晶格耦合。在这里，我们使用太赫兹泵浦和磁光探测的时间分辨光谱技术研究光驱动晶格动力学对CoTiO3磁性的影响。我们发现共振驱动的拉曼活性声子、声子极化子引起的反铁磁磁子激发以及探测器偏振旋转的缓慢增加，所有这些都表明了非本征于磁空间群的对称性破缺。温度依赖性证实了观察到的自旋动力学与磁序有关，并我们认为表面效应可能是可能的机制。我们的太赫兹诱导的自旋-晶格动力学结果表明，外在对称性破缺可能强烈且意外地对块体复杂氧化物中的光驱动现象做出贡献。 显示英文摘要

摘要： Spin-lattice coupling is crucial for understanding the spin transport and dynamics for spintronics and magnonics applications. Recently, cobalt titanate (CoTiO3), an easy-plane antiferromagnet, has been found to host axial phonons with a large magnetic moment, which may originate from spin-lattice coupling. Here, we investigate the effect of light-driven lattice dynamics on the magnetic properties of CoTiO3 using time-resolved spectroscopy with a THz pump and a magneto-optic probe. We found resonantly driven Raman active phonons, phonon-polariton-induced excitation of the antiferromagnetic magnons, and a slow increase in the polarization rotation of the probe, all indicating symmetry breaking that is not intrinsic to the magnetic space group. The temperature dependence confirmed that the observed spin dynamics is related to the magnetic order, and we suggest surface effects as a possible mechanism. Our results of THz-induced spin-lattice dynamics signify that extrinsic symmetry breaking may contribute strongly and unexpectedly to light-driven phenomena in bulk complex oxides.