Zhan Jinxin, Jehle Tom, Stephan Sven, Tiguntseva Ekaterina, Nochowitz Sam S, Groß Petra, Duan Juanmei, Makarov Sergey, Lienau Christoph
Institut für Physik, Carl von Ossietzky Universität, 26129 Oldenburg, Germany.
Department of Nanophotonics and Metamaterials, ITMO University, St. Petersburg 197101, Russia.
Nano Lett. 2024 Dec 11;24(49):15738-15744. doi: 10.1021/acs.nanolett.4c04491. Epub 2024 Nov 28.
Semiconducting halide perovskite nanoparticles support Mie-type resonances that confine light on the nanoscale in localized modes with well-defined spatial field profiles yet unknown near-field dynamics. We introduce an interferometric scattering-type near-field microscopy technique to probe the local electric field dynamics at the surface of a single MAPbI nanoparticle. The amplitude and phase of the coherent light scattering from such modes are probed in a broad spectral range and with high spatial resolution. In the spectral domain, we uncover a Fano resonance with a 2π phase jump. In the near-field dynamics, this Fano resonance gives rise to a destructive interference dip after a few femtoseconds. Mie theory suggests that the interference between electric quadrupole and magnetic dipole modes of the particle, with spectra affected by resonant interband absorption of MAPbI, lies at the origin of this effect. Our results open up a new approach for probing local near-field dynamics of single nanoparticles.
半导体卤化物钙钛矿纳米颗粒支持米氏型共振，这种共振将光限制在具有明确空间场分布的纳米级局部模式中，但其近场动力学尚不清楚。我们引入了一种干涉散射型近场显微镜技术，以探测单个MAPbI纳米颗粒表面的局部电场动力学。在宽光谱范围内以高空间分辨率探测来自此类模式的相干光散射的幅度和相位。在光谱域中，我们发现了一个具有2π相位跃变的法诺共振。在近场动力学中，这种法诺共振在几飞秒后会产生一个相消干涉凹陷。米氏理论表明，颗粒的电四极子和磁偶极子模式之间的干涉，其光谱受MAPbI的共振带间吸收影响，是这种效应的起源。我们的结果为探测单个纳米颗粒的局部近场动力学开辟了一种新方法。
