Recent advances in nanoscale optoelectronic Ge devices have exposed their enormous potential for highly sensitive visible and near-infrared CMOS compatible photodetectors. In this respect, Ge nanowires, due to their nanocylinder resonator shape, have established themselves as a promising platform to significantly enhance the performance of photodetectors. Here, we present a highly sensitive polarity switchable Ge nanowire photodetector embedded in a monolithic and single-crystalline metal–semiconductor nanowire heterostructure. Operated in the negative differential resistance regime, effective dark current suppression up to a factor of 100 is achieved. In this configuration, a bias-switchable positive and negative photoconductance is observed and systematically analyzed. Further, a remarkably strong polarization anisotropy with a maximum TM/TE ratio of 33 was found for positive photoconductance. Most notably, presenting a Ge-based photodetector combining switchable photoconductance and effective dark current suppression may pave the way for advanced applications, including highly resolved imaging and light effect transistors.

中文翻译：

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在负微分电阻机制中运行的纳米级 Ge 光电探测器中的偏置可切换光电导

纳米级光电 Ge 器件的最新进展暴露了它们在高灵敏度可见光和近红外 CMOS 兼容光电探测器方面的巨大潜力。在这方面，锗纳米线由于其纳米圆柱谐振器形状，已成为显着提高光电探测器性能的有前途的平台。在这里，我们提出了一种嵌入在单片和单晶金属-半导体纳米线异质结构中的高灵敏度极性可切换锗纳米线光电探测器。在负微分电阻机制下运行，可实现高达 100 倍的有效暗电流抑制。在这种配置中，观察并系统地分析了偏置可切换的正负光电导。更远，发现正光电导具有非常强的极化各向异性，最大 TM/TE 比为 33。最值得注意的是，结合可切换光电导和有效暗电流抑制的 Ge 基光电探测器可能为高级应用铺平道路，包括高分辨率成像和光效应晶体管。