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Broadband circulators based on directional coupling of one-way waveguides
Wenjun Qiu1, Zheng Wang, Marin Soljačić
1Department of Physics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Optics Express
|November 24, 2011
Summary
New optical circulators overcome bandwidth limits using chiral edge states. This design offers broadband operation and a smaller footprint compared to traditional resonator-based devices.
Area of Science:
- Photonics
- Optical Engineering
- Materials Science
Background:
- Resonator-based optical circulators face inherent bandwidth limitations.
- Quality factors of resonators restrict the operational bandwidth of optical circulators.
Purpose of the Study:
- To propose a novel optical circulator design overcoming bandwidth limitations.
- To explore the use of photonic chiral edge states for broadband optical circulation.
Main Methods:
- Directional coupling between one-way photonic chiral edge states and two-way waveguides.
- Theoretical analysis of the operational bandwidth based on waveguide coupler characteristics.
Main Results:
- The proposed circulator's bandwidth is determined by the directional waveguide coupler.
- Potential for simultaneous broadband operation and a small device footprint.
Conclusions:
- The novel circulator design offers a promising alternative to conventional resonator-based devices.
- This approach enables broadband operation crucial for advanced optical systems.
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