在石墨烯 p-n 结中实现栅极调控的光响应。

Gate-activated photoresponse in a graphene p-n junction.

机构信息

Department of Physics, Harvard University , Cambridge, Massachusetts 02138, United States.

出版信息

Nano Lett. 2011 Oct 12;11(10):4134-7. doi: 10.1021/nl2019068. Epub 2011 Sep 12.

DOI:10.1021/nl2019068

Abstract

We study photodetection in graphene near a local electrostatic gate, which enables active control of the potential landscape and carrier polarity. We find that a strong photoresponse only appears when and where a p-n junction is formed, allowing on-off control of photodetection. Photocurrents generated near p-n junctions do not require biasing and can be realized using submicrometer gates. Locally modulated photoresponse enables a new range of applications for graphene-based photodetectors including, for example, pixilated infrared imaging with control of response on subwavelength dimensions.

摘要

我们研究了在局部静电门附近的石墨烯中的光电探测，这使得对势垒和载流子极性的主动控制成为可能。我们发现，只有当形成 p-n 结时才会出现强的光电响应，从而实现对光电探测的通断控制。在 p-n 结附近产生的光电流不需要偏置，并且可以使用亚微米栅极来实现。局部调制的光电响应使基于石墨烯的光电探测器的一系列新应用成为可能，例如，在亚波长尺寸上控制响应的像素化红外成像。