Extreme space-time optics

In this talk, we explore the cutting-edge realm of photonic time crystals (PTCs) and time-varying photonic media, emphasizing their groundbreaking nonlinear optical properties in the near-infrared spectrum. Our research showcases the spatio-spectral fission of an ultra-fast pulse through a thin film of aluminum zinc oxide with a non-stationary refractive index. We further delve into the time-refraction of optical waves in time-varying slabs, uncovering new geometrical mechanisms for ultrafast frequency blueshift and redshift, and introduce a streak camera design with attosecond resolution capabilities. Turning towards PTC modeling with real-world materials, we investigate dispersive PTCs and reveal hybrid bandgaps with novel excitation channels, paving the way for advancements in polaritonic PTCs. Our findings underscore the transformative potential of these materials in photonic time crystals, on-chip generation of nonclassical states of light, integrated optical neural networks, ultra-fast beam steering, and frequency division multiplexing.