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在双点接触旋转转移装置中的相锁
F B Mancoff1, N D Rizzo, B N Engel
1Technology Solutions Organization, Freescale Semiconductor Inc., Chandler, Arizona 85224, USA. fred.mancoff@freescale.com
Nature
|September 16, 2005
概括
旋转转移扭矩使磁化振荡在距离较近的磁点接触处的相锁定成为可能. 这种同步增强了输出功率,为先进的微波振荡器和存储器设备铺平了道路.
科学领域:
- 这就是Spintronics.
- 凝聚物质物理学 凝聚物质物理学
- 纳米技术 纳米技术
背景情况:
- 旋转转移扭矩是由旋转极化电流与磁性材料之间的相互作用引起的.
- 以前的实验表明,在高电流密度的磁器件中,磁化反转或前行.
- 旋转转移设备对磁性随机访问存储器和微波振荡器具有前景.
研究的目的:
- 为了研究磁化振荡在结合的巨型磁阻 (GMR) 点接触器中的相锁定行为.
- 为了确定接触距离对旋转转移装置的共振频率和输出功率的影响.
主要方法:
- 制造两种80nm直径的GMR点接触器,间距不同 (小于200nm至>400nm).
- 测量由旋转转移电流引起的磁化振荡.
- 分析共振频率和输出功率作为接触距离的函数.
主要成果:
- 对大约200 nm以下的接触间距观察到磁化振荡的相锁定成单个共振.
- 相锁共振频率范围从10GHz以下到24GHz以上.
- 距离较近的接触器 (相锁) 的输出功率大约是距离较远的接触器的两倍,其共振分开.
结论:
- 在距离很近的GMR点接触中,可以实现旋转转移诱导的磁化振荡的相锁定.
- 这种相锁定现象导致输出功率显著增加,这表明了增强微波振荡器应用的潜力.
- 在合的旋转转移装置中控制相锁的能力可以使用于先进的旋转电子应用的大型同步阵列的开发成为可能.
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