论文标题
二维电子系统中用于Terahertz检测的平面光电效应
An in-plane photoelectric effect in two-dimensional electron systems for terahertz detection
论文作者
论文摘要
光电效应在于在物质界面处的潜在屏障上方电子的光激发，并在较大的频率范围内被利用进行光反检测。这个三维过程具有固有的效率低下：光激发电子获得的动量主要与界面平行，而为了留下必须垂直移动的材料。在这里，我们报告发现在二维电子气体内发现的平面光电电启效应。在这种纯粹的量子力学无散射过程中，光电子矩与所需的运动方向完全对齐。 “工作函数”是人为创建和可调的原位。该现象用于构建直接的Terahertz检测器，该检测器产生了巨大的零偏置光响应，超过已知机制的预测超过10倍以上。在二维系统中，光 - 物质相互作用的新方面为覆盖整个Terahertz范围的新一类高效的光电检测器铺平了道路。
The photoelectric effect consists in the photoexcitation of electrons above a potential barrier at a material interface and is exploited for photodetection over a wide frequency range. This three-dimensional process has an inherent inefficiency: photoexcited electrons gain momenta predominantly parallel to the interface, while to leave the material they have to move perpendicular to it. Here, we report on the discovery of an in-plane photoelectric effect occurring within a two-dimensional electron gas. In this purely quantum-mechanical, scattering-free process, photo-electron momenta are perfectly aligned with the desired direction of motion. The "work function" is artificially created and tunable in-situ. The phenomenon is utilized to build a direct terahertz detector, which yields a giant zero-bias photoresponse that exceeds the predictions by known mechanisms by more than 10-fold. This new aspect of light-matter interaction in two-dimensional systems paves the way towards a new class of highly efficient photodetectors covering the entire terahertz range.
