Electrical Spin Injection and Detection in Silicon Nanowires through Oxide Tunnel Barriers
详细信息 查看全文
- 作者：Shixiong Zhang ; Shadi A. Dayeh ; Yan Li ; Scott A. Crooker ; Darryl L. Smith ; S. T. Picraux
- 刊名：Nano Letters
- 出版年：2013
- 出版时间：February 13, 2013
- 年：2013
- 卷：13
- 期：2
- 页码：430-435
- 全文大小：341K
- 年卷期：v.13,no.2(February 13, 2013)
- ISSN：1530-6992
文摘
We demonstrate all-electrical spin injection, transport, and detection in heavily n-type-doped Si nanowires using ferromagnetic Co/Al2O3 tunnel barrier contacts. Analysis of both local and nonlocal spin valve signals at 4 K on the same nanowire device using a standard spin-transport model suggests that high spin injection efficiency (up to 30%) and long spin diffusion lengths (up to 6 渭m) are achieved. These values exceed those reported for spin transport devices based on comparably doped bulk Si. The spin valve signals are found to be strongly bias and temperature dependent and can invert sign with changes in the dc bias current. The influence of the nanowire morphology on field-dependent switching of the contacts is also discussed. Owing to their nanoscale geometry, 5 orders of magnitude less current is required to achieve nonlocal spin valve voltages comparable to those attained in planar microscale spin transport devices, suggesting lower power consumption and the potential for applications of Si nanowires in nanospintronics.