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Microwave synthesizer using an on-chip Brillouin oscillator
Jiang Li1, Hansuek Lee, Kerry J Vahala
1T. J. Watson Laboratory of Applied Physics, California Institute of Technology, Pasadena, California 91125, USA.
Nature Communications
|July 2, 2013
Summary
Researchers developed a chip-based photonic device for highly coherent microwaves. This microcavity oscillator achieves a record low noise floor, advancing compact, low-phase-noise microwave generation.
Area of Science:
- Photonics
- Microwave Engineering
- Quantum Optics
Background:
- Low-phase-noise microwave oscillators are critical for communications, radar, and metrology.
- Photonic-based sources offer superior phase-noise performance compared to electronics, overcoming frequency-dependent attenuation.
- Scaling photonic microwave sources to smaller form factors while maintaining low phase noise presents a significant challenge.
Purpose of the Study:
- To demonstrate a chip-based photonic device for generating highly coherent microwaves.
- To address the challenge of low phase noise in reduced form factor and integrated systems.
- To showcase the first photonic-based microwave frequency synthesizer utilizing a microcavity oscillator.
Main Methods:
- Utilizing a chip-based microcavity device with a high optical quality factor for stability.
- Generating microwaves from a photonic source integrated onto a chip.
- Employing the device as an optical, voltage-controlled oscillator within a frequency synthesizer.
Main Results:
- Achieved generation of highly coherent microwaves from a chip-based photonic device.
- Established a record low electronic white-phase-noise floor for a microcavity-based oscillator.
- Demonstrated the first photonic-based microwave frequency synthesizer with performance comparable to commercial devices.
Conclusions:
- Chip-based microcavity devices with high optical quality factors enable generation of highly coherent microwaves.
- The developed photonic oscillator achieves a record low noise floor, suitable for integrated systems.
- The photonic frequency synthesizer represents a significant advancement in compact, low-phase-noise microwave generation technology.
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