Terahertz waveform generation for S₂₁-parameter measurements using a fiber-coupled optical pulse shaper

Area of Science:

• Terahertz (THz) Science and Technology
• Optoelectronics
• Microwave Engineering

Background:

• Terahertz time-domain spectroscopy (THz-TDS) is a powerful technique for characterizing materials and devices.
• Vector network analysis (VNA) is crucial for understanding signal transmission through electronic components.
• Accurate S21 parameter measurements are essential for evaluating device performance.

Purpose of the Study:

• To present a novel THz time-domain spectroscopy-based vector network analyzer for S21 parameter measurements.
• To demonstrate flexible generation and control of THz waveforms for device testing.
• To validate the system's performance by characterizing a low-noise amplifier.

Main Methods:

• Development of a THz-TDS system incorporating an optical pulse shaper in the emitter arm.
• Fiber-coupling of photoconductive antennas for enhanced flexibility and ease of use.
• Implementation of S21 parameter measurement capabilities for waveguide-coupled devices under test.

Main Results:

• Successful demonstration of pulse-shaping capabilities, realizing all 5 bit combinations of a 0.5 THz signal.
• Ability to precisely set the center wavelength of the generated THz spectrum.
• Application of shaped THz waveforms to successfully test the response of a low-noise amplifier.

Conclusions:

• The developed THz-TDS VNA offers a flexible and versatile platform for characterizing THz devices.
• The integrated optical pulse shaper enables precise control over THz waveform generation.
• This system provides a valuable tool for research and development in THz electronics and photonics.