arXiv subjects

Jules Mercadier

Publications and source records attributed to Jules Mercadier.

5 recordsLinked to original sources

arXiv2026

Random number generation from a self-chaotic broad-area VCSEL

The nonlinear dynamics of transverse and polarization modes of a broad-area vertical-cavity surface-emitting laser (BA-VCSEL) exhibit, without any external perturbation, chaos with high correlation dimension, large bandwidth (BW), and good spectral flatness over a wide range of currents. We leverage this for high bit-rate entropy generation and random number generation (RNG), passing the NIST tests with rates up to 150~Gb/s, and observe a correlation between the correlation dimension and the number of passed NIST tests. The RNG shows consistent performance across a wide range of parameters. In contrast to other setups, our system does not require optical feedback or optical injection to generate chaos, making it simple, compact and robust.

physics.optics↗

arXiv2025

Polarization and tranverse mode nonlinear dynamics in a multimode VCSEL

We theoretically analyze the nonlinear dynamics and routes to chaos in a multimode vertical cavity surface-emitting laser (MM-VCSEL) in free-running operation. Including higher order transverse modes (TMs) results in additional bifurcations at higher currents not found for single-mode VCSELs (SM-VCSELs). The resulting dynamics involve competition between modes with different transverse profiles and polarization and show good qualitative agreement with recent experiments.

physics.optics↗

arXiv2025

Synchronization of complex spatio-temporal dynamics with lasers

Synchronization is the spontaneous alignment of the dynamics of weakly-coupled oscillators. In addition to temporal dynamics like periodic and chaotic oscillations, also the spatio-temporal dynamics of spatially-extended systems like wildlife populations can synchronize. We exploit here the intrinsic spatio-temporal complex dynamics of broad area lasers to demonstrate such synchronization at lab-scale. Broad-area vertical-cavity surface-emitting lasers (BA-VCSELs) exhibit chaos from the nonlinear coupling between laser modes with different spatial profiles and polarization. When coupling two BA-VCSELs, several synchronization and anti-synchronization regimes are observed, highlighting the complex interplay between oscillating modes with different frequencies and spatial patterns. The correlation coefficient varies between 0.2 and 0.9 depending on the dynamics and on the time scale under analysis. Besides its fundamental interest, our experiment with commercial devices marks the first step towards real-world spatial multiplexing in multiple user physical-layer secure communication based on chaos synchronization.

physics.optics↗

arXiv2024

Chaos from a free-running broad-area VCSEL

We experimentally report on the detection of chaos from a free-running commercial broad-area VCSEL without the need for external perturbation such as optical feedback, injection or current modulation. The evolution of nonlinear dynamics leading to chaotic behavior is studied, and the system's complexity is characterized using chaos titration and correlation dimension. We link the occurence of chaos with the complex interplay between the spatial laser modes competition and polarization dynamics.

physics.optics↗

arXiv2024

Optical chaos synchronisation in a cascaded injection experiment

We experimentally study the synchronization of chaos generated by semiconductor lasers in a cascade injection configuration, i.e., a tunable master laser is used to generate chaos by optical injection in a transmitter laser that injects light into a receiver laser. Chaos synchronization between the transmitter and the receiver lasers is achieved with a correlation coefficient of 90 % for a measurement bandwidth up to 35 GHz. Two parameter regions of good synchronization are found, corresponding to the alignment of the oscillation frequencies of the receiver laser with either the transmitter laser or the master laser.

physics.optics↗