In this work, the authors demonstrate a 2 × 2 waveguide-coupler system that produces broadband optical nonreciprocity based on the emulation of nonlinear non-Hermitian time-asymmetric loop. Under operation conditions functional for erbium-doped fiber amplifiers, they obtain 20 dB isolation ratio persisting over the entire gain bandwidth of the amplifier and a wide incident intensity range.
- Yu Sung Choi
- Seung Han Shin
- Jae Woong Yoon
