Laser-induced transient magnons in Sr3Ir2O7 throughout the Brillouin zone
Laser-induced transient magnons in Sr3Ir2O7 throughout the Brillouin zone
复制标题
DOI：
10.1073/pnas.2103696118
复制
发表时间：
2020-02
期刊：
影响因子：
--
通讯作者：
D. Mazzone;D. Meyers;Yue Cao;J. G. Vale;C. D. Dashwood;Youguo Shi;A. James;N. Robinson;Jiaqi Lin;V. Thampy;Yoshikazu Tanaka;Allan S. Johnson;H. Miao;Ruitang Wang;Tadesse A. Assefa;Jungho Kim;D. Casa;R. Mankowsky;D. Zhu;R. Alonso-Mori;Sanghoon Song;H. Yavas;T. Katayama;M. Yabashi;Y. Kubota;S. Owada;Jian Liu;Junji Yang;R. Konik;I. Robinson;John P. Hill;D. McMorrow;M. Först;S. Wall;Xuerong Liu;M. Dean
中科院分区：
文献类型：
--
作者：
D. Mazzone;D. Meyers;Yue Cao;J. G. Vale;C. D. Dashwood;Youguo Shi;A. James;N. Robinson;Jiaqi Lin;V. Thampy;Yoshikazu Tanaka;Allan S. Johnson;H. Miao;Ruitang Wang;Tadesse A. Assefa;Jungho Kim;D. Casa;R. Mankowsky;D. Zhu;R. Alonso-Mori;Sanghoon Song;H. Yavas;T. Katayama;M. Yabashi;Y. Kubota;S. Owada;Jian Liu;Junji Yang;R. Konik;I. Robinson;John P. Hill;D. McMorrow;M. Först;S. Wall;Xuerong Liu;M. Dean
磁态的超快操纵为我们对新量子态的理解和技术应用的进步提供了巨大的希望，但我们目前对瞬态磁性的了解非常有限。我们的工作以Sr3Ir2O7为模型材料阐明了间隙反铁磁体中瞬变磁性的性质。我们发现瞬态磁波动在整个布里渊区被捕获，并且在恢复原始自旋网络所需的时间之外仍然存在。结果在自旋瓶颈效应的背景下解释，其中显式磁衰减通道的存在允许瞬态自旋波的有效热化。尽管磁性的超快操纵对新的物理现象和应用具有很大的前景，但由于我们对超快时间尺度上磁相关如何演变的有限理解，针对特定状态的目标受到阻碍。利用超快共振非弹性x射线散射，我们证明了飞秒激光脉冲可以在有间隙的反铁磁体中激发大波的瞬态磁振子，并且它们持续几皮秒，这与在几乎无间隙的磁体中观察到的相反。我们的工作表明，具有各向同性磁相互作用的材料是实现磁性快速操纵的首选材料。
Significance Ultrafast manipulation of magnetic states holds great promise for progress in our understanding of new quantum states and technical applications, but our current knowledge of transient magnetism is very limited. Our work elucidates the nature of transient magnetism in gapped antiferromagnets using Sr3Ir2O7 as a model material. We find that transient magnetic fluctuations are trapped throughout the entire Brillouin zone while remaining present beyond the time that is required to restore the original spin network. The results are interpreted in the context of a spin-bottleneck effect, in which the existence of an explicit magnetic decay channel allows for an efficient thermalization of transient spin waves. Although ultrafast manipulation of magnetism holds great promise for new physical phenomena and applications, targeting specific states is held back by our limited understanding of how magnetic correlations evolve on ultrafast timescales. Using ultrafast resonant inelastic X-ray scattering we demonstrate that femtosecond laser pulses can excite transient magnons at large wavevectors in gapped antiferromagnets and that they persist for several picoseconds, which is opposite to what is observed in nearly gapless magnets. Our work suggests that materials with isotropic magnetic interactions are preferred to achieve rapid manipulation of magnetism.