Directional excitation without breaking reciprocity

Hamidreza Ramezani,Xiang Zhang,Y Ron Shen,Marc Dubois,Yuan Wang

doi:10.1088/1367-2630/18/9/095001

Abstract

We propose a mechanism for directional excitation without breaking reciprocity. This is achieved by embedding an impedance matched parity-time symmetric potential in a three-port system. The amplitude distribution within the gain and loss regions is strongly influenced by the direction of the incoming field. Consequently, the excitation of the third port is contingent on the direction of incidence while transmission in the main channel is immune. Our design improves the four-port directional coupler scheme, as there is no need to implement an anechoic termination to one of the ports.

Highlights

- Four-port photonic structures with mirrortime reversal symmetries Huanan Li, Roney Thomas, F M Ellis et al
We propose a mechanism for directional excitation without breaking reciprocity
One application of asymmetric transport is directional excitation where the excitation of a third port depends on the direction of incoming field in the main channel

Summary

Introduction

- Four-port photonic structures with mirrortime reversal symmetries Huanan Li, Roney Thomas, F M Ellis et al. We show that by using T symmetry and impedance matching one can obtain highly asymmetric coupling to the third port attached to the main channel.

Results

Conclusion