在石墨烯中使用铁磁范德瓦尔斯接触的和的螺旋注入
Soumya Sarkar1, Saeyoung Oh2, Peter J Newton3
1Department of Materials Science & Metallurgy, University of Cambridge, Cambridge, UK.
概括
研究人员使用新型的-范德瓦尔斯接触器在石墨烯旋转器件中实现了高效的旋转注入. 这一突破消除了挑战介电道障碍的需要,提高了设备的性能和产量.
科学领域:
- 这就是Spintronics.
- 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
背景情况:
- 石墨烯自旋电子设备依赖于高效的自旋注入,通常使用介电道屏障实现.
- 在像石墨烯这样的二维材料上直接生长超薄介电材料是困难和不可靠的,阻碍了设备制造.
- 现有的方法在可靠性和可扩展性方面面临着先进的自旋电子应用的挑战.
研究的目的:
- 研究一种用于在石墨烯侧旋中有效注入旋转的替代方法.
- 探索使用无介电道屏障的铁磁范德瓦尔斯接触.
- 评估使用这种新型接触方法制造的设备的性能和产量.
主要方法:
- 使用铁磁性- (In-Co) 范德瓦尔斯接触器制造石墨烯侧旋.
- 在制造的设备中描述旋转注入效率和磁阻.
- 使用介电道屏障和不使用介电道屏障以及使用非范德瓦尔斯接触器的设备性能比较.
主要成果:
- 在没有介电屏障的情况下,实现了1.5% ± 0.5% (旋转信号~50 Ω) 的显著磁电阻值.
- 证明了超过70%的高工作设备产量.
- 在非范德瓦尔斯接触器的设备中观察到显著较低的磁阻 (~0.2%,旋转信号~3 Ω).
结论:
- 铁磁性-范德瓦尔斯接触器为石墨烯自旋电子装置的自旋注入提供了一种有效和可靠的方法.
- 这种方法绕过了挑战介电道屏障沉积的需要,简化了制造和提高产量.
- In-Co范德瓦尔斯接触器的低接触电阻 (2-5 kΩ) 使它们与补充金属氧化物半导体 (CMOS) 技术兼容.
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