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Dynamic response of modulators based on cascaded-ring-resonator.
Suguru Akiyama1, Shintaro Nomura
1Fujitsu Laboratories Ltd. 10-1 Morinosato-Wakamiya, 243-0122, Japan. akiyama.suguru@jp.fujitsu.com
Optics Express
|October 6, 2012
Summary
Cascaded ring resonator Mach-Zehnder modulators (CRR-MZMs) offer enhanced performance. Optimizing signal delays maximizes bandwidth, enabling higher modulation depth than single-ring designs for frequencies over 25 GHz.
Area of Science:
- Photonics and optical engineering
- Integrated optics and devices
Background:
- Mach-Zehnder modulators (MZMs) are key components in optical communication systems.
- Cascaded ring resonators (RRs) offer potential for enhanced modulator performance.
Purpose of the Study:
- To investigate the dynamic response and optimize the performance of cascaded-ring-resonator-loaded Mach-Zehnder modulators (CRR-MZMs).
- To compare CRR-MZM performance with single-ring-resonator (SRR) modulators.
Main Methods:
- Derivation of the analytical small-signal response using temporal-coupled-mode (TCM) theory.
- Numerical calculations to validate the analytical model.
- Comparative analysis of modulation depth and bandwidth.
Main Results:
- The bandwidth of CRR-MZMs is maximized by optimizing signal delays between adjacent RRs, with the optimal delay being twice the photon lifetime.
- CRR-MZMs demonstrate superior modulation depth compared to SRR modulators for frequencies above 25 GHz, given equivalent refractive index changes.
Conclusions:
- Optimized CRR-MZMs provide a significant advancement in modulator technology.
- These devices offer a promising solution for high-performance optical modulation.
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