Photonic-integrated circuit for continuous-wave THz generation.

Area of Science:

• Photonics
• Terahertz (THz) Technology
• Integrated Optics

Background:

• Continuous-wave (cw) terahertz (THz) generation is crucial for various applications.
• Existing systems often rely on bulky and complex discrete components.
• On-chip integration offers potential for miniaturization and improved control.

Purpose of the Study:

• To demonstrate a novel photonic-integrated circuit for cw THz generation.
• To achieve full control over the THz signal using integrated components.
• To evaluate the performance of the integrated system in a coherent THz photomixing setup.

Main Methods:

• Fabrication of a photonic-integrated circuit comprising two lasers and an optical phase modulator on a single chip.
• Implementation of a unique bidirectional operation technique for THz signal control.
• Utilizing integrated heaters for continuous THz frequency tuning.
• Application in a 1.5 μm optical wavelength coherent cw THz photomixing system.

Main Results:

• Successful demonstration of a photonic-integrated circuit for cw THz generation.
• Achieved full control of the THz signal via the bidirectional operation technique.
• Demonstrated continuous THz frequency tuning over a 570 GHz range using integrated heaters.
• Reached a signal-to-noise ratio of 44 dB at 1.25 THz in a coherent cw THz photomixing system.

Conclusions:

• The demonstrated photonic-integrated circuit provides a compact and efficient solution for cw THz generation.
• The performance of the integrated system is comparable to traditional systems using discrete components.
• This work paves the way for advanced, on-chip THz spectroscopy and imaging systems.