Related papers: Giant second-harmonic generation enabled by bound-…
While two-dimensional (2D) materials have intriguing second-order nonlinearities with ultrahigh coefficient and electrical tunability, their atomic layer thicknesses hinder explorations of other optical frequency-conversions (OFCs) than…
We propose a mean-field model to describe second harmonic generation in a resonator made of a material with zincblende crystalline structure. The model is obtained through an averaging of the propagation equations and boundary conditions.…
We report a systematic investigation into the processes behind a near hundredfold enhanced second harmonic wave generated from a laser-induced air plasma, by examining the temporal dynamics of the frequency conversion processes, and the…
In this letter we experimentally demonstrate second harmonic conversion in the opaque region of a GaAs cavity with efficiencies of the order of 0.1% at 612nm, using 3ps pump pulses having peak intensities of order of 10MW/cm2. We show that…
The search for miniaturized components for nonlinear optical processes needs a way to overcome the efficiency loss due to the effective size reduction of the active medium. We investigate here a combination of a nanosized nonlinear…
We propose and experimentally demonstrate a photonic crystal nanocavity with multiple resonances that can be tuned nearly independently. The design is composed of two orthogonal intersecting nanobeam cavities. Experimentally, we measure…
Periodically poled lithium niobate (PPLN) is a widely used nonlinear optical device for second harmonic generation (SHG). Despite its wide adoption in commercial systems, its bandwidth for SHG is fundamentally limited by the quasi-phase…
We demonstrate phase-matched second-harmonic generation (SHG) from three-dimensional metamaterials consisting of stacked metasurfaces. To achieve phase matching, we utilize a novel mechanism based on phase engineering of the metasurfaces at…
Over the last few years, optical nanoantennas are continuously attracting interest owing to their ability to efficiently confine, localize resonance, and significantly enhanced electromagnetic fields at subwavelength scale. However, such…
We designed, fabricated and tested gallium phosphide (GaP) nano-waveguides for second harmonic generation (SHG). We demonstrate SHG in the visible range around 655 nm using low power continuous-wave pump in the optical communication O-band.…
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…
Parametric oscillation is a fundamental concept that underlies nonlinear wave-matter interactions, leading to generation or amplification of new frequency components. Using a temporal modulation generated by the heterodyne interference of a…
We demonstrate second harmonic generation at telecommunications wavelengths in L3 photonic crystal cavities in (111)-oriented GaAs. The second harmonic power from photonic crystal cavities fabricated in (111)-oriented GaAs is significantly…
Periodically poled lithium niobate (PPLN) waveguide is a powerful platform for efficient wavelength conversion. Conventional PPLN converters however typically require long device lengths and high pump powers due to the limited nonlinear…
We present the design and characterisation of a guided-wave, bright and highly frequency non-degenerate parametric down-conversion source in thin-film lithium niobate. The source generates photon pairs with wavelengths of 815$\,\mathrm{nm}$…
Modern advanced photonic integrated circuits require dense integration of high-speed electro-optic functional elements on a compact chip that consumes only moderate power. Energy efficiency, operation speed, and device dimension are thus…
Optical frequency conversion processes in nonlinear materials are limited in wavelength by the accessible phase matching and the required high pump powers. In this letter, we report a novel broadband phase matching (PM) technique in high…
We demonstrate the highest efficiency ($\sim$80%) second harmonic generation (SHG) of Joule level, 27 femtosecond, high contrast pulses in a type-I lithium triborate (LBO) crystal. In comparison, potassium dihydrogen phosphate (KDP) gives a…
The effect of slow light on second harmonic generation in a periodically poled $\chi^{(2)}$ nonlinear medium is investigated theoretically. A linear $\pi$ phase shifted grating is used to slow the group velocity of the fundamental frequency…
We describe the design, fabrication, and spectroscopy of coupled, high Quality (Q) factor silicon nanobeam photonic crystal cavities. We show that the single nanobeam cavity modes are coupled into even and odd superposition modes, and we…