Sistani Masiar, Bartmann Maximilian G, Güsken Nicholas A, Oulton Rupert F, Keshmiri Hamid, Luong Minh Anh, Momtaz Zahra Sadre, Den Hertog Martien I, Lugstein Alois
Institute of Solid State Electronics, Technische Universität Wien, Gußhausstraße 25-25a, 1040 Vienna, Austria.
The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2AZ, United Kingdom.
ACS Photonics. 2020 Jul 15;7(7):1642-1648. doi: 10.1021/acsphotonics.0c00557. Epub 2020 Jun 30.
Recent advances in guiding and localizing light at the nanoscale exposed the enormous potential of ultrascaled plasmonic devices. In this context, the decay of surface plasmons to hot carriers triggers a variety of applications in boosting the efficiency of energy-harvesting, photocatalysis, and photodetection. However, a detailed understanding of plasmonic hot carrier generation and, particularly, the transfer at metal-semiconductor interfaces is still elusive. In this paper, we introduce a monolithic metal-semiconductor (Al-Ge) heterostructure device, providing a platform to examine surface plasmon decay and hot electron transfer at an atomically sharp Schottky nanojunction. The gated metal-semiconductor heterojunction device features electrostatic control of the Schottky barrier height at the Al-Ge interface, enabling hot electron filtering. The ability of momentum matching and to control the energy distribution of plasmon-driven hot electron injection is demonstrated by controlling the interband electron transfer in Ge, leading to negative differential resistance.
纳米尺度下光的引导和定位方面的最新进展揭示了超尺度等离子体器件的巨大潜力。在此背景下，表面等离子体激元衰变为热载流子引发了在提高能量收集、光催化和光探测效率方面的各种应用。然而，对等离子体热载流子的产生，特别是在金属 - 半导体界面处的转移的详细理解仍然难以捉摸。在本文中，我们介绍了一种单片金属 - 半导体（Al-Ge）异质结构器件，它为研究原子级尖锐肖特基纳米结处的表面等离子体激元衰变和热电子转移提供了一个平台。该栅控金属 - 半导体异质结器件具有对Al-Ge界面处肖特基势垒高度的静电控制能力，从而实现热电子过滤。通过控制Ge中的带间电子转移，展示了动量匹配以及控制等离子体驱动的热电子注入能量分布的能力，进而导致负微分电阻。
