Related papers: A chip-scale second-harmonic source via injection-…
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…
Nonlinear optics, and particularly second harmonic generation (SHG), is increasingly used in many modern disciplines from material characterization in physical sciences to bio-imaging in medicine and optical signal processing in information…
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…
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…
Mid-infrared nanophotonics can be realized using sub-diffractional light localization and field enhancement with surface phonon polaritons in polar dielectric materials. We experimentally demonstrate second harmonic generation due to the…
Quasi-phase-matching for efficient backward second-harmonic generation (BSHG) requires sub-$\rm\mu$m poling periods, a non-trivial fabrication feat. For the first time, we report integrated first-order quasi-phase-matched BSHG enabled by…
Second-harmonic (SH) generation is tremendously important for nonlinear sensing, microscopy and communication system. One of the great challenges of current designs is to enhance the SH signal and simultaneously tune its radiation direction…
Strong second harmonic generation (SHG) in silicon nitride has been extensively studied-among others, in terms of laser-induced SHG enhancement in Si3N4 waveguides. This enhancement has been ascribed to the all-optical poling induced by the…
Optical materials with centrosymmetry, such as silicon and germanium, are unfortunately absent of second-order nonlinear optical responses, hindering their developments in efficient nonlinear optical devices. Here, a design with an array of…
Nano-resonator integrated with two-dimensional materials (e.g. transition metal dichalcogenides) have recently emerged as a promising nano-optoelectronic platform. Here we demonstrate resonatorenhanced second-harmonic generation (SHG) in…
Nonlinear optical phenomena in nanostructured materials have been challenging our perceptions of nonlinear optical processes that have been explored since the invention of lasers. For example, the ability to control optical field…
Second harmonic generation (SHG) microscopy is a valuable tool for optical microscopy. SHG microscopy is normally performed as a point scanning imaging method, which lacks phase information and is limited in spatial resolution by the…
A double-ridge waveguide is designed for efficient and robust second-harmonic generation (SHG) using the thin-film lithium-niobate-on-insulator (LNOI) platform. Perfect phase matching (PhM) is achieved between the fundamental waveguide mode…
We present a versatile confocal microscopy setup for optical second harmonic generation (SHG) and multi-photon spectroscopy that enables polarization-resolved studies of semiconductor bulk crystals and low-dimensional structures. The system…
High complexity, dense integrated nanophotonic circuits possessing strong nonlinearities are desirable for a breadth of applications in classical and quantum optics. In this work, we study natural phase matching via modal engineering in…
We report on strong enhancement of mid-infrared second harmonic generation (SHG) from SiC nanopillars due to the resonant excitation of localized surface phonon-polaritons within the Reststrahlen band. The magnitude of the SHG peak at the…
Inversion symmetry eliminates the second-order nonlinear responses in materials commonly used in silicon photonics with electric-dipole approximation. The lack of effective methods to induce the second-order nonlinearity in silicon photonic…
On-chip coherent visible and near-infrared (NIR) light generation has broad applications in metrology, bio-sensing, and quantum information. High-Q microresonators are ideal candidates for generating light across such broad wavelength…
Boosting nonlinear frequency conversion in extremely confined volumes remains a key challenge in nano-optics, nanomedicine, photocatalysis, and background-free biosensing. To this aim, field enhancements in plasmonic nanostructures are…
We investigate Second Harmonic Generation from individual silicon nanowires and study the influence of resonant optical modes on the far-field nonlinear emission. We find that the polarization of the Second Harmonic has a size-dependent…