论文标题
磁性半导体中超快自旋动力学的直接光学探测
Direct optical probing of ultrafast spin dynamics in a magnetic semiconductor
论文作者
论文摘要
我们首次发现了磁性半导体中巨型自旋极化子的出生和生长的自旋动力学。为此，我们开发了一种新的测量技术，该技术首次可以直接访问旋转动力学，而与该过程中涉及的声子和载体无关。此外，我们首次在自旋极化子的特定情况下首次求解了Landau-Liftshitz方程，该方程非常适合我们的数据，并首次证明了自旋极性生长在顺磁相中冷却样品时急剧减慢。最后，进行了依赖温度的蒙特卡洛模拟，这与观察到的放缓非常吻合，这表明魏斯场中的波动在磁性材料中的光引起的自旋相干产生中起决定性作用。这些结果为旋转动态调查提供了一种新工具和新的见解。
We uncovered for the first time the spin dynamics involved in the birth and growth of giant spin polarons in a magnetic semiconductor. For this purpose, we developed a new measurement technique, which for the first time provides direct access to the spin dynamics, irrespective of phonons and carriers involved in the process. Moreover, we solved for the first time the Landau-Liftshitz equation in the specific scenario of spin polarons, which fits our data excellently, and demonstrates for the first time that the spin polaron growth slows down dramatically when the sample is cooled in the paramagnetic phase. Finally, temperature dependent Monte Carlo simulations were performed, which are in excellent agreement with the observed slowdown, which demonstrates for the first time that fluctuations in the Weiss field play a decisive role in spin coherence generation induced by light in magnetic materials. These results offer a new tool and new insight for spin dynamics investigations.
