拉曼活性轴向手性声子诱导的超快磁化

中文摘要 AI 辅助

轴向手性声子携带角动量并表现出异常大的磁矩，为控制量子材料的时间反演对称性和磁性质提供了新的自由度。虽然红外活性轴向声子可通过圆偏振太赫兹脉冲高效激发至大振幅，但其应用可能受限于短寿命、小穿透深度、低空间分辨率以及光学源的可获得性有限。在此，我们报道CeF3中的一种轴向拉曼活性声子模式表现出显著的磁矩和极长的寿命，该寿命与顺磁自旋动力学更为匹配。轴向声子布居通过近红外激光脉冲（即光学离心机）的旋转线偏振光进行共振驱动，这是一种此前从未应用于固体的相干控制方案。通过时间分辨法拉第旋转观测到的声子驱动磁化强度随入射功率呈二次方标度，并在高温下迅速减小，这与多体自旋-声子耦合产生的声子逆法拉第效应一致。我们的发现为利用广泛可及光源产生的整形激光脉冲来操纵相干轴向手性声子和超快自旋电子学开辟了新途径。

英文摘要

Axial chiral phonons, which carry angular momentum and exhibit unusually large magnetic moments, provide a new degree of freedom for controlling the time-reversal symmetry and magnetic properties of quantum materials. While infrared-active axial phonons are efficiently excited to large amplitudes by circularly polarized terahertz pulses, their application may be constrained by short lifetimes, small penetration depths, low spatial resolution, and limited availability of optical sources. Here, we report that an axial Raman-active phonon mode in CeF3 exhibits a significant magnetic moment and an exceedingly long lifetime that more closely matches the paramagnetic spin dynamics. The axial phonon population is resonantly driven by a near-infrared laser pulse with rotating linear polarization, known as an optical centrifuge, a coherent control scheme never applied to solids before. The phonon-driven magnetization observed by time-resolved Faraday rotation scales quadratically with incident power and rapidly decreases at high temperatures, consistent with phonon inverse Faraday effect from many-body spin-phonon coupling. Our findings open a new avenue for using shaped laser pulses from widely accessible light sources to manipulate coherent axial chiral phonons and ultrafast spintronics.

发表机构

• Rice University（莱斯大学）
• The University of British Columbia（不列颠哥伦比亚大学）
• Texas Tech University（德克萨斯理工大学）
• The University of Texas at Arlington（德克萨斯大学阿灵顿分校）

机构由 AI 辅助整理，请以论文原文为准。