Epsilon-Near-Zero-Slot Waveguides and Their Applications in Ultrafast Laser Beam Steering

摘要

Recent research on epsilon-near-zero (or index-near-zero) materials has revealed their promising applications in optoelectronics. We explore a novel waveguide structure, namely "epsilon-near-zero-slot waveguide", by utilizing transparent conducting oxides as the active medium, which can be tuned between epsilon-near-zero and epsilon-far-from-zero by accumulation carriers, resulting in sharp effective index change. We propose laser beam steering by taking advantage of this epsilon-near-zero-slot waveguide structure. With about 60° steering angle being achieved, this waveguide structure has the advantages of ultra high speed and compact dimension, as well as easy fabrication.