image: Figure | Chiral EP enhanced electro-optic tuning and low energy directional optical interconnects. a. Schematics of the chiral microring resonator (MRR), with lithographically defined low loss asymmetric Mie scatterer (Inset), which mediates asymmetric coupling between clockwise (CW) and counterclockwise (CCW) modes. Local nano-heater tunes inter-scatter phase, leading to the tunable asymmetric coupling strength in the device. b. 3-dimentional imaging laser microscope captured image of the non-Hermitian photonic modulation coupled to add-drop type microring resonator, manufactured through a foundry wafer run. c. Exemplary application scenario of the chiral electro-optic response enabled unidirectional data flow between transmitting electronic integrated circuits (EICs) and receiving EICs. In conventional MRMs, duplicated circuit topologies for transmitting and receiving terminals are required to avoid crosstalk (grey).
Credit: by Maleki, A., Heindl, M.B., Xin, Y. et al.
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.”
Journal
Light Science & Applications
Article Title
Strategies to enhance THz harmonic generation combining multilayered, gated, and metamaterial-based architectures