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Compact-sized high-modulation-efficiency silicon Mach-Zehnder modulator based on a vertically dipped depletion
Optics Letters
|July 1, 2014
Summary
We developed a compact silicon Mach-Zehnder (MZ) modulator using a vertically dipped PN depletion junction (VDJ) phase shifter. This device achieves high-speed operation and shows potential for future chip-level integration.
Area of Science:
- Photonics
- Integrated Optics
- Semiconductor Devices
Background:
- Silicon Mach-Zehnder (MZ) modulators are crucial for optical communication.
- Existing modulators face challenges in size and integration.
Purpose of the Study:
- To present a small-sized, depletion-type silicon MZ modulator.
- To utilize a vertically dipped PN depletion junction (VDJ) phase shifter.
- To demonstrate CMOS compatibility for chip-level integration.
Main Methods:
- Fabrication of a depletion-type silicon MZ modulator.
- Incorporation of a 100 μm long VDJ phase shifter.
- Characterization of VπLπ, bandwidth, extinction ratio, and insertion loss.
Main Results:
- Achieved a VπLπ of ~0.6 V·cm and a 3 dB bandwidth of ~50 GHz.
- Demonstrated extinction ratios of 6 dB and 5.3 dB at 40 and 50 Gb/s.
- Measured on-chip insertion loss of 3 dB, with phase-shifter loss of 1.88 dB/100 μm.
Conclusions:
- The VDJ scheme enables compact depletion-type MZ modulators.
- The device is a potential candidate for future chip-level optical integration.
- Further optimization can minimize optical propagation loss.
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