Quantitative sampling of atomic-scale electromagnetic waveforms
Quantitative sampling of atomic-scale electromagnetic waveforms
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DOI：
10.1038/s41566-020-00720-8
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发表时间：
2020-11-16
期刊：
影响因子：
35
通讯作者：
Repp, J.
中科院分区：
文献类型：
--
作者：
Peller, D.;Roelcke, C.;Repp, J.
定制的纳米结构可以将电磁波限制在极亚波长的体积内，为光波传感和控制开辟了新的途径，直到亚分子分辨率。原子光-物质相互作用关键取决于近场的绝对强度和精确的时间演化，这可能受到量子力学效应的强烈影响。然而，测量原子尺度的场瞬变仍然遥不可及。在这里，我们介绍了定量原子尺度的波形采样光波扫描隧道显微镜解决尖端限制近场瞬态。我们的无参数校准采用单分子开关作为原子尺度的电压标准。虽然远场到近场转移的显着特点遵循经典电动力学，我们开发了一个全面的理解与时间相关的密度泛函理论的原子尺度的波形。模拟验证了我们的校准，并确认单电子隧穿确保最小的反作用的测量过程中的电磁场。我们的观察访问纳米光电子学的未知领域，局部量子动力学确定飞秒原子近场。
Tailored nanostructures can confine electromagnetic waveforms in extremely sub-wavelength volumes, opening new avenues in lightwave sensing and control down to sub-molecular resolution. Atomic light-matter interaction depends critically on the absolute strength and the precise time evolution of the near field, which may be strongly influenced by quantum-mechanical effects. However, measuring atom-scale field transients has remained out of reach. Here we introduce quantitative atomic-scale waveform sampling in lightwave scanning tunnelling microscopy to resolve a tip-confined near-field transient. Our parameter-free calibration employs a single-molecule switch as an atomic-scale voltage standard. Although salient features of the far-to-near-field transfer follow classical electrodynamics, we develop a comprehensive understanding of the atomic-scale waveforms with time-dependent density functional theory. The simulations validate our calibration and confirm that single-electron tunnelling ensures minimal back-action of the measurement process on the electromagnetic fields. Our observations access an uncharted domain of nano-opto-electronics where local quantum dynamics determine femtosecond atomic near fields.