在石墨烯中采用热载体辅助的内在光响应
Nathaniel M Gabor1, Justin C W Song, Qiong Ma
1Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Science (New York, N.Y.)
|October 8, 2011
概括
研究人员在石墨烯p-n连接处观察到独特的光伏模式,表明热载体传输主导着光电子反应. 这一发现可以推进太阳能采集技术.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 纳米技术纳米技术
背景情况:
- 石墨烯的独特电子特性使其成为先进光电子设备的候选者.
- 了解石墨烯p-n连接中的内在光响应机制对于设备应用至关重要.
研究的目的:
- 为了研究双门石墨烯p-n连接的内在光电子反应.
- 阐明观察到的光响应背后的主导机制.
主要方法:
- 制造高质量的单层和双层石墨烯p-n连接装置.
- 在p-n接口使用850nm的局部激光激发.
- 分析光伏模式作为门电压和空间/密度依赖的函数.
主要成果:
- 观察到显著的六倍光伏模式,取决于门电压.
- 证明非局部热载体运输,而不是光伏效应,决定了光响应.
- 确定了一个长寿且空间分布的热载体群体.
结论:
- 非局部热载体运输是石墨烯p-n连接处内在光响应的主要机制.
- 这种现象为热载体辅助热电技术开辟了可能性.
- 有效的太阳能采集应用的潜力.
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