Related papers: Second harmonic generation in germanium quantum we…
We report terahertz (THz) second harmonic generation (SHG) in superconductors (SC) with inversion symmetric equilibrium states that forbid even-order nonlinearities. Such SHG signal is observed in single-pulse emission by periodic driving…
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…
We have investigated second harmonic generation (SHG) from Ag-coated LiNbO3 (LN) core-shell nanocuboids and found that giant SHG can occur via deliberately designed double plasmonic resonances. By controlling the aspect ratio, we can tune…
Achieving compact and efficient visible laser sources is crucial for a wide range of applications. However traditional semiconductor laser technology faces difficulties in producing high-brightness green light, leaving a green gap in…
We demonstrate second order optical nonlinearity in a silicon architecture through heterogeneous integration of single-crystalline gallium nitride (GaN) on silicon (100) substrates. By engineering GaN microrings for dual resonance around…
The optimal design for infrared second harmonic generation (SHG) is determined for a GaAs-based quantum device using a recently developed genetic approach. Both compositional parameters and electric field are simultaneously optimized, and…
Monolayer transition-metal dichalcogenides (TMDCs) present high second-order optical nonlinearity, which is extremely desirable for, e.g., frequency conversion in nonlinear photonic devices. On the other hand, the atomic thickness of 2D…
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…
Nonreciprocal devices that allow the light propagation in only one direction are indispensable in photonic circuits and emerging quantum technologies. Contemporary optical isolators and circulators, however, require large size or strong…
We report on nonlinear frequency conversion from the telecom range via second harmonic generation (SHG) and third harmonic generation (THG) in suspended gallium nitride slab photonic crystal (PhC) cavities on silicon, under continuous-wave…
We theoretically predict efficient optical second-harmonic generation (SHG) from a few hundred nanometer thick slab consisting of a quadratic nonlinear anisotropic medium whose linear principal permittivities are, at the fundamental…
Second-harmonic generation (SHG) is a powerful surface-specific probe for centrosymmetric materials, with broad relevance to energy and biological interfaces. Plasmonic nanomaterials have been extensively utilized to amplify this nonlinear…
A new concept for second-harmonic generation (SHG) in an optical nanocircuit is proposed. We demonstrate both theoretically and experimentally that the symmetry of an optical mode alone is sufficient to allow SHG even in centro-symmetric…
Second harmonic generation (SHG) is a non-linear optical process, where two photons coherently combine into one photon of twice their energy. Efficient SHG occurs for crystals with broken inversion symmetry, such as transition metal…
By employing a pump-probe technique for enhanced spectral mapping of the dynamics in nonlinear frequency conversion, we demonstrate that photo-induced second-harmonic generation (SHG) in silicon nitride (Si3N4) microresonators can persist…
Semiconductor nanowires (NWs) are promising for realizing various on-chip nonlinear optical devices, due to their nanoscale lateral confinement and strong light-matter interaction. However, high-intensity pulsed pump lasers are typically…
We have studied on optical second harmonic generations (SHGs) from atomically thin MoTe2 flakes with 2H and 1T' phases. From 2H-MoTe2 samples with odd (even) numbers of layers, strong (negligible) SHGs are observed due to the…
Silicon-based nonlinear metasurfaces were implemented only with third-order nonlinearity due to the crystal centrosymmetry and the efficiencies are considerably low, which hinders their practical applications with low-power lasers. Here, we…
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…
Optical second harmonic generation (SHG) is a nonlinear optical effect widely used for nonlinear optical microscopy and laser frequency conversion. Closed-form analytical solution of the nonlinear optical responses is essential for…