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We refer to Canonical Resonant Four-Wave-Mixing when only four (three in the degenerate case) modes of the cavity are able to interact through this parametric process; thereby inhibiting competing parametric processes. This condition is achieved in the recently introduced photonic crystal parametric oscillator, Marty et al. Nat. Photonics, 15, 53 (2021). Here, we discuss extensively the properties of this parametric source and compare the design with other geometries of photonic crystal resonators. Based on a statistical study over more than 100 resonators and 10 parametric oscillators, robustness against fabrication tolerances is assessed, performances are evaluated in terms of average values and their dispersion, and the dependence on the main parameters is shown to follow the theoretical scaling. The lowest pump power at threshold is $\approx$40 $\mu$W and we show the existence of a minimum value of the cavity photon lifetime as a condition for parametric oscillation, which is related to three photon absorption.

We theoretically and experimentally investigate type II second harmonic generation in III-V-on-insulator wire waveguides. We show that the propagation direction plays a crucial role and that longitudinal field components can be leveraged for robust and efficient conversion. We predict that the maximum theoretical conversion is larger than that of type I second harmonic generation for similar waveguide dimensions and reach an experimental conversion efficiency of 12%/W, limited by the propagation loss.

We theoretically and experimentally investigate type II second harmonic generation in III-V-on-insulator wire waveguides. We show that the propagation direction plays a crucial role and that longitudinal field components can be leveraged for robust and efficient conversion. We predict that the maximum theoretical conversion is larger than that of type I second harmonic generation for similar waveguide dimensions and reach an experimental conversion efficiency of 12%/W, limited by the propagation loss.

We report a new class of optical parametric oscillators, based on a 20-µm-long semiconductor photonic crystal cavity and operating at telecom wavelengths. Because the confinement results from Bragg scattering, the optical cavity contains a few modes, approximately equispaced in frequency. Parametric oscillation is reached when these high-quality-factor modes are thermally tuned into a triply resonant configuration, whereas any other parametric interaction is strongly suppressed. The lowest pump power threshold is estimated to be 50–70?µW. This source behaves as an ideal degenerate optical parametric oscillator, addressing the needs in the field of quantum optical circuits and paving the way towards the dense integration of highly efficient nonlinear sources of squeezed light or entangled photons pairs.

The third-order Kerr nonlinear response in gallium phosphide nanoscale waveguides is measured through continuous-wave (CW) four-wave mixing. The extracted nonlinear coefficient ranges from about 800  W^−1 m^−1 to 1400  W^−1 m^−1, consistently with an estimated material nonlinearity n_2=3.5×10^−18  W^−1 m^2. The roles of the residual absorption and the related thermal effects are discussed.

The most-awaited convergence of microelectronics and photonics promises to bring about a revolution for on-chip data communications and processing. Among all the optoelectronic devices to be developed, power-efficient nanolaser diodes able to be integrated densely with silicon photonics and electronics are essential to convert electrical data into the optical domain. Here, we report a demonstration of ultracompact laser diodes based on one-dimensional (1D) photonic crystal (PhC) nanocavities made in InP nanoribs heterogeneously integrated on a silicon-waveguide circuitry. The specific nanorib design enables an efficient electrical injection of carriers in the nanocavity without spoiling its optical properties. Room-temperature continuous-wave (CW) single-mode operation is obtained with a low current threshold of 100 µA. Laser emission at 1.56 µm in the silicon waveguides is obtained with wall-plug efficiencies greater than 10%. This result opens up exciting avenues for constructing optical networks at the submillimetre scale for on-chip interconnects and signal processing.

Heat dissipation is improved in nonlinear III-V photonic crystal waveguides owing to the hybrid III-V/Silicon integration platform, allowing efficient four-wave mixing in the continuous-wave regime. A conversion efficiency of −17.6  dB is demonstrated with a pump power level below 100 mW in a dispersion-engineered waveguide with a flat group index of 28 over a 10 nm bandwidth.

High-quality (Q) factor indium phosphide (InP)-based 1D photonic crystal nanobeam cavities are fabricated on silicon on insulator waveguides. Through the optimization of the fabrication process, the intrinsic Q factor of these fully encapsulated nanocavities is demonstrated to attain values higher than 100,000. Experimental and numerical investigations are carried out on the impact, on the Q factor, of the strength of the evanescent wave coupling between the cavity and the waveguide. We reveal that this coupling can result in a modification of the electromagnetic field distribution in the resonant mode, which gives rise up to a factor 4 reduction in the intrinsic Q factor for the structures under study.

We demonstrate the generation of an octave-spanning supercontinuum in InGaP membrane waveguides on a silicon substrate pumped by a 1550-nm femtosecond source. The broadband nature of the supercontinuum in these dispersion-engineered high-index-contrast waveguides is enabled by dispersive wave generation on both sides of the pump as well as by the low nonlinear losses inherent to the material. We also measure the coherence properties of the output spectra close to the pump wavelength and find that the supercontinuum is highly coherent at least in this wavelength range.

We report on the modeling and experimental characterization of an InP-based photonic crystal wire cavity laser bonded to a silicon wafer. Simulations give an insight into the variation of the resonant mode frequency and the dependence of the Q-factor on the geometrical parameters of the laser cavity. Calculated and measured Q-factors are of the order of 10^4. A low threshold laser operation is demonstrated.

We present the experimental demonstration of a novel class of hybrid III–V-on-silicon microlasers. We show that by coupling a silicon cavity to a III–V waveguide, the interaction between the propagating mode in the III–V waveguide and the cavity mode in the silicon resonator results in high, narrowband reflection back into the III–V waveguide, forming a so-called resonant mirror. By combining two such mirrors and providing optical gain in the III–V wire between these two mirrors, laser operation can be realized. This optically pumped device measures 55 by 2 μm, requires microwatt-level threshold pump power, and shows single-mode laser emission with a side-mode suppression ratio of up to 39 dB.