Related papers: Probing optical anapoles with fast electron beams
The discrete and charge-separated nature of matter - electrons and nuclei - results in local electrostatic fields that are ubiquitous in nanoscale structures and are determined by their shape, material, and environment. Such fields are…
A quantum mechanical scattering theory for relativistic, highly focused electron beams near nanoscopic platelets is presented, revealing a new excitation mechanism due to the electron wave scattering from the platelet edges. Radiative…
Electron energy-loss spectroscopy (EELS) offers a window to view nanoscale properties and processes. When performed in a scanning transmission electron microscope, EELS can simultaneously render images of nanoscale objects with…
We have theoretically studied how the azimuthal phase structure of an electron vortex beam excites surface plasmons on metal particles of different geometries as observed in electron energy loss spectroscopy. To do so, we have developed a…
Few inventions have shaped the world like the incandescent bulb. While Edison used thermal radiation from ohmically heated conductors, some noble metals exhibit "cold" electroluminescence (EL) in percolation films, tunnel diodes,…
For homogenous isotropic dielectric nanospheres with incident plane waves, Cartesian electric and toroidal dipoles can be tunned to cancel each other in terms of far-field scattering, leading to the effective anopole excitation. At the same…
We investigate the kinetic-energy spectrum of electrons emitted from an excited many-electron system, often called photo-electron spectrum (PES). We are particularly interested on the impact of resonant modes of the system on PES. To this…
The optical properties of a stack of GaN/AlN quantum discs (QDiscs) in a GaN nanowire have been studied by spatially resolved cathodoluminescence (CL) at the nanoscale (nanoCL) using a Scanning Transmission Electron Microscope (STEM)…
Scanning transmission electron microscopy (STEM) has advanced rapidly in the last decade thanks to the ability to correct the major aberrations of the probe forming lens. Now atomic-sized beams are routine, even at accelerating voltages as…
Optically-induced magnetic resonances in non-magnetic media have unlocked magnetic light-matter interactions and led to new technologies in many research fields. Previous proposals for the levitation of nanoscale particles without…
By studying the scattering of normally incident planewaves by a single nanowire, we reveal the indispensable role of toroidal multipole excitation in multipole expansions of radiating sources. It is found that for both p-polarized and…
Nanoscale materials usually can trap light and strongly interact with it leading to many photonic device applications. The light-matter interactions are commonly probed by optical spectroscopy, which, however, have some limitations such as…
Using a time-resolved optically-pumped scanning optical microscopy technique we demonstrate the laser-driven excitation and propagation of spin waves in a 20-nm film of a ferromagnetic metallic alloy Galfenol epitaxially grown on a GaAs…
The electromagnetic response of a nanoparticle of an ion-doped polymeric elastic insulator, commonly called as an electret, is considered in the continuum model of a uniformly charged elastic sphere. The spectral formulae for the frequency…
The presence of electron energy loss (EELS) peak is proposed theoretically in molybdenum disulfide (MoS2) nanosheets. Using density functional theory simulations and calculations, one EELS peak is identified in the visible energy range, for…
We suggest to excite dipole-forbidden transitions in quantum-mechanical systems by using appropriately designed optical nanoantennas. The antennas are tailored such that their near-field contains sufficiently strong contributions of…
We study the role of collective surface excitations in the electron relaxation in small metal particles. We show that the dynamically screened electron-electron interaction in a nanoparticle contains a size-dependent correction induced by…
Structured light provides unique opportunities to spatially tailor the electromagnetic field of laser beams. This includes the possibility of a sub-wavelength spatial separation of their electric and magnetic fields, which would allow…
Nonradiating electromagnetic configurations in nanostructures open new horizons for applications due to two essential features: lack of energy losses and invisibility to the propagating electromagnetic field. Such radiationless…
We experimentally observe the dipole scattering of a nanoparticle using a high numerical aperture (NA) imaging system. The optically levitated nanoparticle provides an environment free of particle-substrate interaction. We illuminate the…