Exceptional points (EPs) in non-Hermitian systems are drawing attention for their ability to enhance light-matter interactions. Here we explore the EP's contribution to the electro-optic tunability, modulation and nonreciprocal responses.
Here we implement fully mechanically stable and electro-optically tunable EP system, with two lithographically defined asymmetric Mie scatterers and electro-optic tuning phase and amplitude. These scatterers disrupt rotational symmetry and enable dynamic tuning across a chiral EP using a nanoscale local heater. This setup allows for precise, phase-sensitive control of coupling between clockwise (CW) and counterclockwise (CCW) modes, leading to enhanced electro-optic amplitude modulation.
Dr. Lee, the first author, discussed his enthusiasm for the work:"Our approach makes major strides in chiral silicon photonics for several reasons. Firstly, we developed a nano-heater aligned to one arm of the micro-resonator, achieving highly localized heating rather than heating the entire ring. Addressing the challenge posed by a large thermal diffusion length (>10 µm), this innovation allows for deterministic, dynamic tuning of chirality. Secondly, our precise phase-only control enables unique inter-scatter phase tuning, enhancing electro-optic amplitude modulation in ways never previously predicted or observed."
"Finally, this chiral electro-optic modulator could revolutionize photonic integrated circuits, reducing energy consumption and simplifying circuit design. Potential applications span neuromorphic computing, secure quantum networks, and advanced sensors for smart infrastructure."
