摘要
We investigate the structural,static magnetic and damping properties in two Mn-deficient magnetic Weyl semimetal Co-Mn-Ga(CMG) alloy films,i.e.,Co_(55)Mn_(18)Ga_(27)(CMG1) and Co_(50)Mn_(18)Ga_(32)(CMG2),which were epitaxially grown on MgO(001) substrates.CMG1 has a mixing phase of B2and L21,larger saturation magnetization(M_(s) ~760 emu/cm^(3)),stronger in-plane magnetic anisotropy.CMG2 has an almost pure B2phase,smaller M_(s)(~330 emu/cm^(3)),negligible in-plane magnetic anisotropy.Time-resolved magneto-optical Kerr effect results unambiguously demonstrate an obvious perpendicular standing spin wave(PSSW) mode in addition to the Kittel mode for both of the CMG films.The intrinsic damping constant is about 0.0055 and 0.015 for CMG1 and CMG2,respectively,which are both significantly larger than that of the stoichiometric CMG(i.e.,Co_(2)MnGa)film reported previously.In combination with the first-principles calculations,the intrinsic damping properties of the Mn-deficient CMG films can be well explained by considering the increase of density of states at the Fermi level,reduction of M_(s),and excitation of the PSSW mode.These findings provide a new clue to tuning the magnetic damping of the magnetic Weyl semimetal film through slight off-stoichiometry.
作者
陈家瑞
龚钰婷
陆显扬
张晨宇
胡勇
王铭志
时钟
付帅
蔡宏灵
刘若柏
袁源
卢羽
刘天宇
游彪
徐永兵
杜军
Jia-Rui Chen;Yu-Ting Gong;Xian-Yang Lu;Chen-Yu Zhang;Yong Hu;Ming-Zhi Wang;Zhong Shi;Shuai Fu;Hong-Ling Cai;Ruo-Bai Liu;Yuan Yuan;Yu Lu;Tian-Yu Liu;Biao You;Yong-Bing Xu;Jun Du(National Laboratory of Solid State Microstructures and Department of Physics,Nanjing University,Nanjing 210093,China;York-Nanjing Joint Center(YNJC)for Spintronics and Nano-Engineering,School of Electronic Science and Engineering,Nanjing University,Nanjing 210093,China;College of Sciences,Northeastern University,Shenyang 110819,China;School of Physics Science and Engineering,Tongji University,Shanghai 200092,China;Collaborative Innovation Center of Advanced Microstructures,Nanjing 210093,China)
基金
supported by the National Key R&D Program of China (Grant Nos.2022YFA1403602 and 2021YFB3601600)
the National Natural Science Foundation of China (Grant Nos.51971109,U22A20117,51771053,52001169,11874199,12104216,and 12241403)
the Natural Science Foundation of Jiangsu Province of China (Grant No.BK20200307)。
