531 citations · 1.2k across the 19 of their papers we have counts for
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Cathodoluminescence Enhancement Mechanisms in Silica Microspheres
Hadar Aharon, Zahava Barkay, Sophie Meuret +1
Cathodoluminescence (CL) enables optical-frequency analysis of samples with nanometer resolutions, originating from the interaction of a focused electron beam with radiative electr…
Light's symmetry, asymmetry, and their role in nonlinear optics and ultrafast phenomena
Ofer Neufeld, Matan Even Tzur, Ofer Kfir +2
The analysis of symmetries is extremely useful across science. In Physics, symmetries are used to derive conservation laws and selection rules for transitions in interacting system…
Sub-Terahertz Nearfields for Electron-Pulse Compression
Yarden Mazor, Ofer Kfir
The advent of ultrafast science with pulsed electron beams raised the need in controlling the temporal features of the electron pulses. One promising suggestion is the nano-selecti…
Modulation of Cathodoluminescence Emission by Interference with External Light
Valerio Di Giulio, Ofer Kfir, Claus Ropers +1
Spontaneous processes triggered in a sample by free electrons are commonly regarded as incoherent, and therefore unable to interfere with external light sources. Here, we challenge…
Implementing strong interference in ultrathin film top absorbers for tandem solar cells
Yifat Piekner, Hen Dotan, Anton Tsyganok +4
Strong interference in ultrathin film semiconductor absorbers on metallic back reflectors has been shown to enhance the light harvesting efficiency of solar cell materials. However…
Ultrafast high-harmonic nanoscopy of magnetization dynamics
Sergey Zayko, Ofer Kfir, Michael Heigl +4
Light-induced magnetization changes, such as all-optical switching, skyrmion nucleation, and intersite spin transfer, unfold on temporal and spatial scales down to femtoseconds and…
Chiral high-harmonic generation and spectroscopy on solid surfaces using polarization-tailored strong fields
Tobias Heinrich, Marco Taucer, Ofer Kfir +4
Strong-field methods in solids enable new strategies for ultrafast nonlinear spectroscopy and provide all-optical insights into the electronic properties of condensed matter in rec…
Probing chirality with inelastic electron-light scattering
Tyler R. Harvey, Jan-Wilke Henke, Ofer Kfir +4
Circular dichroism spectroscopy is an essential technique for understanding molecular structure and magnetic materials, but spatial resolution is limited by the wavelength of light…
Controlling free electrons with optical whispering-gallery modes
Ofer Kfir, Hugo Lourenço-Martins, Gero Storeck +5
Free-electron beams serve as uniquely versatile probes of microscopic structure and composition, and have repeatedly revolutionized atomic-scale imaging, from solid-state physics t…
Nanoscale Magnetic Imaging using Circularly Polarized High-Harmonic Radiation
Ofer Kfir, Sergey Zayko, Christina Nolte +10
This work demonstrates nanoscale magnetic imaging using bright circularly polarized high-harmonic radiation. We utilize the magneto-optical contrast of worm-like magnetic domains i…
High-order harmonics with frequency-varying polarization within each harmonic
Avner Fleischer, Ofer Kfir, Pavel Sidorenko +1
We predict high-order harmonics in which the polarization within the spectral bandwidth of each harmonic varies continuously and significantly. For example, the interaction of coun…
Generation of phase-matched circularly-polarized extreme ultraviolet high harmonics for magnetic circular dichroism spectroscopy
Ofer Kfir, Patrik Grychtol, Emrah Turgut +10
Circularly-polarized extreme UV and X-ray radiation provides valuable access to the structural, electronic and magnetic properties of materials. To date, this capability was availa…
Does high harmonic generation conserve angular momentum?
Avner Fleischer, Ofer Kfir, Tzvi Diskin +2
High harmonic generation (HHG) is a unique and useful process in which infrared or visible radiation is frequency up converted into the extreme ultraviolet and x ray spectral regio…