[22p-13M-1~17] 3.15 Optics and Photonics English Session

3:15 PM - 3:30 PM JST(6:15 AM - 6:30 AM UTC)English Presentation

[22p-13M-7] Robust optical non-reciprocity enabled by emulating nonlinear time-asymmetric loop around an exceptional-point singularity

〇Jae Woong Yoon¹, Yu Sung Choi¹, Seung Han Shin¹, Seungmin Lee¹, Miji Kim¹ (1.Dept. of Physics, Hanyang University)

Keywords:

Waveguides,Optical fibre,Optical non-reciprocity

We experimentally demonstrate a remarkably simple waveguide structure that emulates nonlinear time-asymmetric loop around an exceptional-point singularity, producing robust optical non-reciprocity. The proposed structure consists of five lumped optical components – two linear attenuators, two saturable amplifiers, and one 2-by-2 passive coupler. Under routinely-obtainable, moderate operation conditions, the structure produces the non-reciprocal transmission effect with 20 dB isolation ratio persisting over the entire gain bandwidth of the amplifiers and over a remarkably wide incident-intensity range from 0.1 mW to 10 kW. We provide a theoretical model of a dissipative saturable amplifier that quantitatively captures the key experimental results and explains underlying physics of the observed effect.