Space- and Time-Varying Photonics: from Photonic Time Crystals to Quantum Light - College of Engineering - Purdue University

The ability to achieve strong and rapid modulations of materials’ electromagnetic (EM) properties have significant implications in classical and quantum optics. Large in magnitude and ultra-fast changes in the EM response in a periodic or even single-step manner can lead to profound effects, including time-refraction and time-reflection. Recent advances in photonic materials, namely, transparent conducting oxides (TCOs) enable substantial and ultrafast light-induced response at optical frequencies, within the near-zero-index (NZI) spectral range. Such NZI materials enable extreme optics, where both phase velocity and wavelength are anomalously large, ideally diverge, while the group velocity approaches zero. The project aims at investigating space- and time-varying metastructures and photonic time crystals (PTCs), with a particular focus on exploring light emission from quantum sources. We will study novel nonlinear and quantum phenomena in such media, explore the generation and amplification of entangled states, and design of two-dimensional cluster states. We envision innovative applications such as PTC-based lasers and PTC-enhanced quantum light.