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Title: Non-reciprocal parity-time symmetry breaking based on magneto-optical and gain/loss double ring resonators

In this paper, we explore the operation of a nonreciprocal non-Hermitian system consisting of a lossy magneto-optical ring resonator coupled to another ring resonator with gain and loss, and we demonstrate that such a system can exhibit non-reciprocity-based broken parity-time (PT) symmetry and supports one-way exceptional points. The nonreciprocal PT-phase transition is analyzed with the use of both analytical tools based on coupled-mode theory and two-dimensional finite element method simulations. Our calculations show that the response of the system strongly depends on the regime of operation – broken or preserved PT-symmetry. This response is leveraged to show that the system can operate as an optical isolator or a one-way laser with functionality tuned by adjusting loss/gain in the second ring resonator. The proposed system can thus be promising for device applications such as magnetically or even optically switchable non-reciprocal devices and one-way micro-ring lasers.

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Award ID(s):
1809915
NSF-PAR ID:
10369479
Author(s) / Creator(s):
; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optical Materials Express
Volume:
12
Issue:
4
ISSN:
2159-3930
Page Range / eLocation ID:
Article No. 1453
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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