钇铁石榴石(yttrium iron garnet,YIG)的自旋输运特性一直是自旋电子学的研究重点之一.Bi作为YIG最常见的掺杂元素,其薄膜Bi_(x)Y_(3-x)Fe_(5)O_(12)的磁光特性已经被广泛研究.但Bi^(3+)取代Y^(3+)对YIG自旋输运的影响规律还没有被系统...钇铁石榴石(yttrium iron garnet,YIG)的自旋输运特性一直是自旋电子学的研究重点之一.Bi作为YIG最常见的掺杂元素,其薄膜Bi_(x)Y_(3-x)Fe_(5)O_(12)的磁光特性已经被广泛研究.但Bi^(3+)取代Y^(3+)对YIG自旋输运的影响规律还没有被系统地研究过.本文利用溶液旋涂法制备了不同掺杂比的Bi_(x)Y_(3-x)Fe_(5)O_(12)薄膜,并研究Bi掺杂对YIG薄膜形貌结构和自旋输运性能的影响.结果表明Bi掺杂没有改变YIG的晶体结构,掺杂比上升令薄膜的吸收强度增大,带隙减小.XPS表明了Bi^(3+)和Bi^(2+)的存在.Bi掺杂在自旋输运上的调控体现在Bi_(x)Y_(3-x)Fe_(5)O_(12)薄膜的磁振子扩散长度相比纯YIG薄膜有所减小.同时研究发现Pt/Bi_(x)Y_(3-x)Fe_(5)O_(12)薄膜中依然可以检测到明显的自旋霍尔磁电阻,并在x=0.3时振幅最大.展开更多
In the previous study of longitudinal spin Seebeck effect（LSSE）, the thermal gradient was often generated by inserting the sample between the cool bath and the hot bath. For practical use, this method is too cumbers...In the previous study of longitudinal spin Seebeck effect（LSSE）, the thermal gradient was often generated by inserting the sample between the cool bath and the hot bath. For practical use, this method is too cumbersome to be easily integrated into modern electrical circuits. Since the laser can be easily focused into a small region, it will be more convenient and friendly to the integrated circuit. In this paper, we systematically investigate the LSSE and spin Hall magnetoresistance（SMR） of the Pt/Y_3 Fe_5 O_（12） heterostructure under focused laser-heating. We find that the extremely large voltage of inverse spin Hall effect（VISHE） can be obtained by reducing the diameter of laser or increasing the number of light spots.Meanwhile, even under the illumination of the ultraviolet light which will excite the electron from the valence band to the conduction band in yttrium iron garnet（YIG）, the magnitude of SMR is nearly constant. It indicates that the spin transport behavior of the adjacent Pt is independent of the electron configuration of YIG. The laser-heating method to generate LSSE will be very promising for modern integrated electronic circuits and will promote the application of spin caloritronics in practice.展开更多
Magneto-electric properties of the magnetic domains local areas of bismuth-substituted yttrium iron garnet films are investigated. The electromagneto-optical (EMO) scanning method was used in our experiments when prob...Magneto-electric properties of the magnetic domains local areas of bismuth-substituted yttrium iron garnet films are investigated. The electromagneto-optical (EMO) scanning method was used in our experiments when probing by laser beam various sites of separate magnetic domains of the film. Registered in our experiments the nonlinear and linear components of EMO effect does not remain to constants at optical scanning of various points of the magnetic domain. I.e. the local EMOE picture from the separate sites of the domain must be more informative than an averaged one in the multidomain case.展开更多
以共沉淀法制备了纳米级铋-钇铁柘榴石粉末,并压锭成块材进行微波测试,因钇铁柘榴石块材烧结温度>1400℃,无法顺利导入低温多层共烧陶瓷制程(LTCC),本研究以掺杂铋元素进入柘榴石晶体内的方式,使块材烧结温度大幅下降,同时不降低其...以共沉淀法制备了纳米级铋-钇铁柘榴石粉末,并压锭成块材进行微波测试,因钇铁柘榴石块材烧结温度>1400℃,无法顺利导入低温多层共烧陶瓷制程(LTCC),本研究以掺杂铋元素进入柘榴石晶体内的方式,使块材烧结温度大幅下降,同时不降低其在微波应用上的性质.实验结果显示,随着掺杂铋元素的增加,块材的烧结温度最大可降至850℃,而微波应用于滤波器的亚铁磁共振(Ferrimagnetic magnetic resonance)特性在测量后证实并未遭受破坏.展开更多
文摘钇铁石榴石(yttrium iron garnet,YIG)的自旋输运特性一直是自旋电子学的研究重点之一.Bi作为YIG最常见的掺杂元素,其薄膜Bi_(x)Y_(3-x)Fe_(5)O_(12)的磁光特性已经被广泛研究.但Bi^(3+)取代Y^(3+)对YIG自旋输运的影响规律还没有被系统地研究过.本文利用溶液旋涂法制备了不同掺杂比的Bi_(x)Y_(3-x)Fe_(5)O_(12)薄膜,并研究Bi掺杂对YIG薄膜形貌结构和自旋输运性能的影响.结果表明Bi掺杂没有改变YIG的晶体结构,掺杂比上升令薄膜的吸收强度增大,带隙减小.XPS表明了Bi^(3+)和Bi^(2+)的存在.Bi掺杂在自旋输运上的调控体现在Bi_(x)Y_(3-x)Fe_(5)O_(12)薄膜的磁振子扩散长度相比纯YIG薄膜有所减小.同时研究发现Pt/Bi_(x)Y_(3-x)Fe_(5)O_(12)薄膜中依然可以检测到明显的自旋霍尔磁电阻,并在x=0.3时振幅最大.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11604265,51471134,51572222,and 11704386)the Fundamental Research Funds for the Central Universities,China(Grant Nos.3102018zy044 and 3102017jc01001)
文摘In the previous study of longitudinal spin Seebeck effect（LSSE）, the thermal gradient was often generated by inserting the sample between the cool bath and the hot bath. For practical use, this method is too cumbersome to be easily integrated into modern electrical circuits. Since the laser can be easily focused into a small region, it will be more convenient and friendly to the integrated circuit. In this paper, we systematically investigate the LSSE and spin Hall magnetoresistance（SMR） of the Pt/Y_3 Fe_5 O_（12） heterostructure under focused laser-heating. We find that the extremely large voltage of inverse spin Hall effect（VISHE） can be obtained by reducing the diameter of laser or increasing the number of light spots.Meanwhile, even under the illumination of the ultraviolet light which will excite the electron from the valence band to the conduction band in yttrium iron garnet（YIG）, the magnitude of SMR is nearly constant. It indicates that the spin transport behavior of the adjacent Pt is independent of the electron configuration of YIG. The laser-heating method to generate LSSE will be very promising for modern integrated electronic circuits and will promote the application of spin caloritronics in practice.
文摘Magneto-electric properties of the magnetic domains local areas of bismuth-substituted yttrium iron garnet films are investigated. The electromagneto-optical (EMO) scanning method was used in our experiments when probing by laser beam various sites of separate magnetic domains of the film. Registered in our experiments the nonlinear and linear components of EMO effect does not remain to constants at optical scanning of various points of the magnetic domain. I.e. the local EMOE picture from the separate sites of the domain must be more informative than an averaged one in the multidomain case.
文摘以共沉淀法制备了纳米级铋-钇铁柘榴石粉末,并压锭成块材进行微波测试,因钇铁柘榴石块材烧结温度>1400℃,无法顺利导入低温多层共烧陶瓷制程(LTCC),本研究以掺杂铋元素进入柘榴石晶体内的方式,使块材烧结温度大幅下降,同时不降低其在微波应用上的性质.实验结果显示,随着掺杂铋元素的增加,块材的烧结温度最大可降至850℃,而微波应用于滤波器的亚铁磁共振(Ferrimagnetic magnetic resonance)特性在测量后证实并未遭受破坏.
