The optical equivalent of the quantum mechanical oscillator is demonstrated in a photonic crystal cavity, owing to the balance of the background dispersion and a bichromatic potential. Consequently, several equi‐spaced resonances with large loaded Q factors are obtained within a very tiny volume. A detailed statistical analysis is carried out by exploiting the complex reflection spectra measured with Optical Coherent Tomography. The log‐normal distribution of the intrinsic Q‐factors is centered at 0.7 million. The device is made of Ga0.5In0.5P in order to suppress the two photon absorption in the Telecom spectral range considered here. This is crucial to turn the strong localization of light into ultra‐efficient parametric interactions.

We present the demonstration of an integrated frequency modulated continuous wave LiDAR on a silicon platform. The waveform calibration, the scanning system, and the balanced detectors are implemented on a chip. Detection and ranging of a moving hard target at upto 60 m with less than 5 mW of output power is demonstrated in this paper. Index Terms-Coherent LiDAR, frequency modulated continuous wave LiDAR, laser range finder, optical sensing and sensors, photonic integrated circuits. Patrick Feneyrou received the Ph.D. degree in nonlinear spectroscopy. Since 1998, he is with the Thales Research and Technology, Palaiseau, France. Since 2003, he is in charge of the theoretical analysis, system simulation, and development of proof of concept of LiDAR systems. He has developed several LiDAR systems for laser anemometry, temperature sensing, range finding, and velocimetry. Jérôme Bourderionnet received the Ph.D. degree in laser physics. Since 2001, he has been working with the

Oscillators in the GHz frequency range are key building blocks for telecommunication and positioning applications. Operating directly in the GHz while keeping high frequency stability and compactness, is still an up-to-date challenge. Recently, optomechanical crystals have demonstrated GHz frequency modes, thus gathering prerequisite features for using them as oscillators. Here we report on the demonstration, in ambient atmospheric conditions, of an optomechanical oscillator designed with an original concept based on bichromaticity. This oscillator is made of InGaP, a low loss and TPA-free piezoelectric material which makes it valuable for optomechanics. Self-sustained oscillations directly at 3 GHz are routinely achieved with a low optical power threshold of 40 µW and short-term linewidth narrowed down to 100 Hz in agreement with phase noise measurements (-110 dBc/Hz at 1 MHz from the carrier) for free running optomechanical oscillators.

We introduce a nanoscale photonic platform based on gallium phosphide. Owing to the favorable material properties, peak power intensity levels of 50 GW∕cm 2 are safely reached in a suspended membrane. Consequently, the field enhancement is exploited to a far greater extent to achieve efficient and strong light-matter interaction. As an example, parametric interactions are shown to reach a deeply nonlinear regime, revealing cascaded fourwave mixing leading to comb generation and high-order soliton dynamics.

Original waveforms and optimized signal processing are proposed for frequency-modulated continuous-wave lidar for range finding, velocimetry, and laser anemometry. For range finding, the aim of this signal processing is to extend lidar range and reduce ambiguities. Moreover, the effect of moderate atmospheric turbulence on lidar efficiency is analyzed for infinite and finite targets, taking into account wind-induced bistatism. For laser anemometry, the aim is to measure air speed at the shortest distance farther than the rotor-induced turbulent volume around the helicopter and to avoid parasitic echoes coming from clouds or hard targets in the vicinity of a helicopter.

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Frequency-modulated continuous-wave lidar is evaluated for range finding, velocimetry, and laser anemometry. An original signal processing and waveform calibration for range finding leads to a reduction of computational effort while preserving capability for long-range measurement. Multiple target distance measurement is also demonstrated. For laser anemometry, the aim is to avoid parasitic echoes in the vicinity of a helicopter and to measure the air speed at the shortest distance farther than the rotor-induced turbulent volume around the helicopter. Flight tests of this functionality and vortex ring state warning are demonstrated.

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.