External-Magnetic-Field-Free Spintronic Terahertz Strong-Field Emitter  

作　　者：Shaojie Liu Zejun Ren Peng Chen Sai Chen Mingxuan Zhang Zehao Yang Deyin Kong Jinguang Wang Yifei Li Jinglong Ma Xin Lu Baolong Zhang Zhongkai Liu Xiufeng Han Caihua Wan Yutong Li Ranjan Singh Xiaojun Wu 

机构地区：[1]School of Cyber Science and Technology,Beihang University,Beijing 100191,China [2]School of Electronic and Information Engineering,Beihang University,Beijing 100083,China [3]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [4]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China [5]Zhangjiang Laboratory,Shanghai 201204,China [6]Songshan Lake Materials Laboratory,Dongguan 523808,Guangdong,China [7]Division of Physics and Applied Physics,School of Physical and Mathematical Sciences,Nanyang Technological University,Singapore 637371,Singapore [8]School of Physical Science and Technology,ShanghaiTech University,Shanghai 201210,China [9]Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan 430074,China

出　　处：《Ultrafast Science》2024年第4期1-9,共9页超快科学(英文)

基　　金：supported by the National Key R&D Program of China(2022YFA1604402);the National Natural Science Foundation of China(11827807,92250307,and 62005140);the Open Project Program of Wuhan National Laboratory for Optoelectronics No.2022WNLOKF006.

摘　　要：Intense terahertz(THz)radiation in free space has immense potential for regulating material state,accelerating electrons,producing biological effects,and so on.However,the high cost and challenges involved in constructing strong-field THz sources have limited their developments,making it difficult for the potential applications of strong-field THz radiation to be widely adopted.Spintronic THz emitters(STEs)with numerous merits such as high efficiency,ultrabroadband,ease of integration,and low cost have become ubiquitous,but the majority of these emitters require stable operation in the presence of external magnets,limiting their applications,particularly in generating strong fields that necessitate large-sized samples.Here,we demonstrate the feasibility of generating strong-field THz radiation in 4-inch antiferromagnetic material–ferromagnetic metal(IrMn_(3)[2 nm]/Co_(20)Fe_(60)B_(20)[2 nm]/W[2 nm])without external magnetic field driving.Under the excitation of a Ti:sapphire femtosecond laser amplifier with a 35-fs pulse duration and a 1-kHz repetition rate,we obtain strong-field THz radiation from our STEs with a pulse duration of~110 fs,and a spectrum covering up to~10 THz.Further scaling up the pump laser energy up to 55 mJ with a pulse duration of~20 fs and a repetition rate of 100 Hz provided by the Synergetic Extreme Condition User Facility,the radiated THz electric field strength from the external-magnetic-free 4-inch STEs can exceed 242 kV/cm with a pulse duration of~230 fs,a spectrum covering up to~14 THz,and a single pulse energy of 8.6 nJ measured by a calibrated pyroelectric detector.Our demonstrated external-magnetic-field-free high-field STEs have some unique applications such as producing sub-cycle ultrashort strong THz fields in huge size emitters under the excitation of high-energy light sources,accelerating the development of THz science and applications.

关 键 词：AMPLIFIER PUMP REPETITION 

分 类 号：TN2[电子电信—物理电子学]