Related papers: Type I and type II second harmonic generation of c…
Since the first observation of second harmonic generation (SHG), there have been extensive studies on this nonlinear phenomenon not only to clarify its physical origin but also to realize unconventional functionalities. Nonetheless, a…
Second-harmonic generation (SHG) is a second-order nonlinear optical process that is not allowed in media with inversion sym-metry. However, due to the broken symmetry at the surface, surface SHG still occurs, but is generally small. We…
The generation process of second harmonic (SH) radiation from holes periodically arranged on a metal surface is investigated. Three main modulating factors affecting the optical response are identified: the near-field distribution at the…
We report the observations of unexpected layer-dependent, strong, and anisotropic second harmonic generations (SHGs) in atomically thin ReS2. Appreciable (negligible) SHGs are obtained from even (odd) numbers of ReS2 layers, which is…
Metallic nanostructures exhibit strong nonlinear-optical response at surface plasmon resonances, where the light-matter coupling efficiency is enhanced. An active modulation of this response can be realized by means of an external magnetic…
Second Harmonic Generation (SHG) of single-layer monochalcogenides, such as GaSe and InSe, has been recently reported [2D Mater. 5 (2018) 025019; J. Am. Chem. Soc. 2015, 137, 79947997] to be extremely strong with respect to bulk and…
Second harmonic generation is considered in lossy negative-index metamaterials. It is shown that energy transfer from fundamental to harmonic takes place in the entire sample for the range of phase mismatch values. Note that in conventional…
Second harmonic generation (SHG) is a powerful optical tool for identifying non-centrosymmetric crystalline structures. Here, we analyze SHG in multilayer graphenes (MLG), with a focus on its dependence on the stacking order, encapsulation…
The emerging field of silicon photonics seeks to unify the high bandwidth of optical communications with CMOS microelectronic circuits. Many components have been demonstrated for on-chip optical communications, including those that utilize…
Second harmonic generation (SHG), as one of the most significant \c{hi}(2) nonlinear optical processes, plays crucial roles in a broad variety of optical and photonic applications. Designing various delicate schemes to achieve highly…
We study surface second-harmonic generation (SHG) from a singular plasmonic structure consisting of touching metallic wires. We use the technique of transformation optics and relate the structure to a rather simpler geometry, a slab…
Second harmonic generation (SHG) is forbidden in centrosymmetric molecular materials. However, a signal is frequently observed from interfaces where the symmetry is broken. Whereas the effect can be phenomenologically accommodated, an ab…
Dynamic phase-only beam shaping with a liquid crystal spatial light modulator is a powerful technique for tailoring the beam's intensity profile or wave front. While shaping and controlling the light field is a highly researched topic,…
We report on the experimental and theoretical investigation of magnetic-field-induced second harmonic generation (SHG) and two-photon absorption (TPA) of excited exciton states ($n \geq 3$) of the yellow series in Cu$_2$O. In this…
Second harmonic generation (SHG) is a fundamental nonlinear optical phenomenon widely used both for experimental probes of materials and for application to optical devices. Even-order nonlinear optical responses including SHG generally…
We study the nonlinear process of second harmonic generation in photonic time-crystals, materials with refractive index that varies abruptly and periodically in time, and obtain the phase matching condition for this process. We find…
Rydberg excitons in $\mathrm{Cu_2O}$ simultaneously give rise to two very different optical responses under resonant two-photon excitation: a coherent second-harmonic signal mediated by the excitonic second order susceptibility tensor…
We report the observation of optical second harmonic generation (SHG) in single-layer indium selenide (InSe). We measure a second harmonic signal of $>10^3$ $\textrm{cts/s}$ under nonresonant excitation using a home-built confocal…
An analytical theory of the nonlinear electromagnetic response of a two-dimensional (2D) electron system in the second order in the electric field amplitude is developed. The second-order polarizability and the intensity of the second…
It is generally argued that material classes with inversion symmetry do not produce bulk dipole related second harmonic generation (SHG). So, SHG is then either ascribed to surface effects or bulk related electric quadrupole or magnetic…