Laser-induced ultrafast spin dynamics in ErFeO3
Laser-induced ultrafast spin dynamics in ErFeO3
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DOI：
10.1103/physrevb.84.104421
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发表时间：
2011-09-12
影响因子：
3.7
通讯作者：
Rasing, Th.
中科院分区：
文献类型：
--
作者：
de Jong, J. A.;Kimel, A. V.;Rasing, Th.
利用100-fs的激光脉冲，我们已经能够激发和探测稀土正铁氧体ErFeO3的自旋动力学。在较宽的温度范围内进行了研究，重点研究了补偿点T-comp近似于47K的附近，以及小于或类似于T小于或类似于99k的86K区间内的自旋取向转变区。激光脉冲激发的自旋进动在研究的大部分温度范围内存在，但在自旋重定向区域附近尤其强烈。在这个区域，激光脉冲也引起了超快的自旋重定向。通过改变激光脉冲通量，可以改变重定向振幅和重定向速度。我们发现激光诱导的ErFeO3的自旋动力学部分是由加热引起的，部分是由反法拉第效应引起的。与其他稀土正铁氧体的类似实验结果相比，我们发现激光诱导的自旋重定向速度明显降低。我们将这一发现归因于Er3+ 4f电子与晶格之间较弱的电子-声子耦合。
Using 100-fs optical laser pulses, we have been able to excite and probe spin dynamics in the rare-earth orthoferrite ErFeO3. The investigation was performed in a broad temperature range with the focus on the vicinities of the compensation point T-comp approximate to 47K and the spin reorientation transition region in the interval 86K less than or similar to T less than or similar to 99 K. Spin precession excited by the laser pulse was present in a large part of the investigated temperature range, but was especially strong near the spin reorientation region. In this region the laser pulse also caused an ultrafast spin reorientation. By changing the laser pulse fluence, we could vary both the reorientation amplitude and the reorientation speed. We show that the laser-induced spin dynamics in ErFeO3 is caused in part by heating and in part by the inverse Faraday effect. Comparing to the results of similar experiments in other rare-earth orthoferrites, we found the speed of the laser-induced spin reorientation to be significantly lower. We attribute this finding to the weaker electron-phonon coupling of the Er3+ 4f electrons with the lattice.