Reddy Harsha, Wang Kun, Kudyshev Zhaxylyk, Zhu Linxiao, Yan Shen, Vezzoli Andrea, Higgins Simon J, Gavini Vikram, Boltasseva Alexandra, Reddy Pramod, Shalaev Vladimir M, Meyhofer Edgar
School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907, USA.
Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
Science. 2020 Jul 24;369(6502):423-426. doi: 10.1126/science.abb3457. Epub 2020 Jun 4.
Hot carriers in plasmonic nanostructures, generated via plasmon decay, play key roles in applications such as photocatalysis and in photodetectors that circumvent bandgap limitations. However, direct experimental quantification of steady-state energy distributions of hot carriers in nanostructures has so far been lacking. We present transport measurements from single-molecule junctions, created by trapping suitably chosen single molecules between an ultrathin gold film supporting surface plasmon polaritons and a scanning probe tip, that can provide quantification of plasmonic hot-carrier distributions. Our results show that Landau damping is the dominant physical mechanism of hot-carrier generation in nanoscale systems with strong confinement. The technique developed in this work will enable quantification of plasmonic hot-carrier distributions in nanophotonic and plasmonic devices.
通过等离子体激元衰变产生的等离子体纳米结构中的热载流子，在光催化等应用以及规避带隙限制的光电探测器中发挥着关键作用。然而，迄今为止，尚未有对纳米结构中热载流子稳态能量分布的直接实验量化。我们展示了通过将适当选择的单个分子捕获在支持表面等离激元极化激元的超薄金膜和扫描探针尖端之间而创建的单分子结的输运测量，这种测量可以提供等离子体热载流子分布的量化。我们的结果表明，朗道阻尼是在具有强限制的纳米尺度系统中热载流子产生的主要物理机制。这项工作中开发的技术将能够量化纳米光子和等离子体器件中的等离子体热载流子分布。
