在铁磁半导体结构中的电流诱导的域壁切换
M Yamanouchi1, D Chiba, F Matsukura
1Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577, Japan.
Nature
|April 2, 2004
概括
研究人员展示了一种使用电流磁性信息存储的新方法. 这种方法显著降低了所需的电流密度,为未来的数据存储技术提供了一个有希望的替代方案.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 电气工程 电气工程
背景情况:
- 磁性信息存储传统上使用磁场进行磁化逆转,这需要超密度设备的高磁场强度.
- 目前在金属系统中使用电流进行磁化逆转的方法需要高电流密度 (10^7-10^8 A cm^-2),超过集成电路的极限.
- 在金属系统中,域墙操纵也需要高电流密度,这对实际应用提出了挑战.
研究的目的:
- 研究一种使用电流在显著降低密度的磁化逆转的替代方法.
- 探索铁磁半导体结构对于磁性信息编码的潜力.
- 为了克服当前磁性存储技术中高电流密度的局限性.
主要方法:
- 使用铁磁半导体结构来诱导磁化逆转.
- 使用电流脉冲来切换域壁,从而逆转磁化.
- 在没有外部磁场的情况下研究了磁化逆转.
主要成果:
- 通过使用电流脉冲在铁磁半导体中的域壁切换来证明磁化逆转.
- 在电流密度低于10^5 A cm^-2的情况下实现了磁化逆转,这与现有方法相比显著减少.
- 确定了缓慢的开关速度和低铁磁过渡温度作为当前限制.
结论:
- 在铁磁半导体中,通过电脉冲在降低的电流密度来逆转磁化是可行的.
- 开发的方法为未来的磁性信息存储应用提供了潜在的途径.
- 需要进一步的研究来解决切换速度和铁磁过渡温度的局限性,以便实际实施.
相关概念视频
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A moving charge or a current creates a magnetic field in the surrounding space, in addition to its electric field. The magnetic field exerts a force on any other moving charge or current that is present in the field. Like an electric field, the magnetic field is also a vector field. At any position, the direction of the magnetic field is defined as the direction in which the north pole of a compass needle points.
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01:13Magnetic Force Between Two Parallel Currents
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01:23Induced Electric Fields
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01:27Induced Electric Fields: Applications
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01:28Magnetostatic Boundary Conditions
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