Laser-induced transient magnons in Sr <sub>3</sub> Ir <sub>2</sub> O <sub>7</sub> throughout the Brillouin zone
D. G. Mazzone, D. Meyers, Yue Cao, J. G. Vale, C. D. Dashwood, Youguo Shi, A. J. A. James, Neil J. Robinson, Jiaqi Lin, Vivek Thampy, Yoshikazu Tanaka, Allan S. Johnson, H. Miao, Ruitang Wang, Tadesse A. Assefa, Jungho Kim, D. Casa, Roman Mankowsky, Diling Zhu, Roberto Alonso‐Mori, Sanghoon Song, Hasan Yavaş, Tetsuo Katayama, Makina Yabashi, Yuya Kubota, Shigeki Owada, Jian Liu, Junji Yang, Robert Konik, Ian Robinson, J. P. Hill, D. F. McMorrow, M. Först, Simon Wall, Xuerong Liu, M. P. M. Dean
Abstract
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.