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Novel cascaded injection-locked 1.55-mum VCSELs with 66 GHz modulation bandwidth
Optics Express
|June 25, 2009
Summary
Cascading optically injection-locked VCSELs significantly boosts direct modulation bandwidth from 10 GHz to 66 GHz. This novel configuration offers tailorable bandwidth for advanced optical communication systems.
Area of Science:
- Optoelectronics
- Semiconductor devices
- Optical communications
Background:
- Vertical-cavity surface-emitting lasers (VCSELs) are crucial for optical communications.
- Achieving high direct modulation bandwidth in VCSELs is essential for higher data rates.
- Existing VCSELs have limited free-running modulation bandwidths.
Purpose of the Study:
- To demonstrate a novel cascaded configuration of optically injection-locked (COIL) VCSELs.
- To achieve a wide and tailorable direct modulation bandwidth.
- To explore different cascading configurations for optimizing modulation bandwidth.
Main Methods:
- Utilizing a cascaded configuration of optically injection-locked VCSELs.
- Investigating various VCSEL cascading arrangements.
- Analyzing the impact of different configurations on modulation bandwidth.
Main Results:
- Achieved a direct modulation bandwidth of up to 66 GHz.
- Significantly enhanced the bandwidth from an original free-running 10 GHz.
- Demonstrated tailorable modulation response through cascading.
Conclusions:
- The COIL VCSEL configuration is effective for wide and tailorable modulation bandwidth.
- This technique shows potential for scaling to meet future communication demands.
- Optimized cascading offers a pathway to advanced optical modulation capabilities.
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