摘要
We investigate the ultrafast spin dynamics of an antiferromagnet in a ferromagnet/antiferromagnet heterostructure Fe/GdFeO_(3) via an all-optical method.After laser irradiation,the terahertz spin precession is hard to be excited in a bare GdFeO_(3) without spin reorientation phase but efficiently in Fe/GdFeO_(3).Both quasi-ferromagnetic and impurity modes,as well as a phonon mode,are observed.We attribute it to the optical modification of interfacial exchange coupling between Fe and GdFeO3.Moreover,the excitation efficiency of dynamics can be modified significantly via the pump laser influence.Our results elucidate that the interfacial exchange coupling is a feasible stimulation to efficiently excite terahertz spin dynamics in antiferromagnets.It will expand the exploration of terahertz spin dynamics for antiferromagnet-based opto-spintronic devices.
作者
李娜
汤进
苏磊
柯亚娇
张伟
谢宗凯
孙瑞
张向群
何为
成昭华
Na Li;Jin Tang;Lei Su;Ya-Jiao Ke;Wei Zhang;Zong-Kai Xie;Rui Sun;Xiang-Qun Zhang;Wei He;Zhao-Hua Cheng(State Key Laboratory of Magnetism and Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;Songshan Lake Materials Laboratory,Dongguan 523808,China)
基金
Project supported by the National Key Research Program of China(Grant Nos.2018YFF01010303,2017YFB0702702,and 2016YFA0300701)
the National Natural Sciences Foundation of China(Grant Nos.52031015,1187411,51427801,and 51871235)
the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant Nos.QYZDJ-SSW-JSC023,KJZD-SW-M01,and ZDYZ2012-2).
