Robust Nonlinear Photonics and Integrated Photonics

Light-matter interaction lies at the heart of modern photonics, enabling both the control of quantum states in integrated platforms and the creation of new states of light through nonlinear processes. As photonic systems scale in complexity, a key challenge emerges: performance must remain stable despite fabrication variations, environmental fluctuations, and control imperfections that are inherent to real-world devices. In this seminar, I will present a framework for robust photonic design that enhances device reliability without compromising efficiency or scalability.

On the integrated photonics front, I will introduce detuning-modulated composite segmentation (DMCS) - a method inspired by composite pulse concepts but re-engineered for waveguide-based architectures. This approach enables high-fidelity transformations even when coupling coefficients deviate from their design values, overcoming a primary bottleneck in achieving scalable quantum and classical photonic circuits.

In the domain of nonlinear photonics, I will show how these robust-design principles extend to parametric light generation. Specifically, I will present a new class of composite schemes for spontaneous parametric down-conversion, which significantly suppress sensitivity to phase-matching errors while maintaining high brightness. This marks the first successful adaptation of composite strategies to the SU(1,1) symmetry of nonlinear optical processes, offering enhanced performance for entangled photon sources and broadband frequency conversion.

Together, these advances demonstrate how robust design concepts can unlock the next generation of stable, scalable, and high-performance photonic technologies, spanning both integrated circuitry and nonlinear light generation.