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Related Experiment Video

Updated: Jul 5, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

Precisely tunable continuous-wave terahertz source with interferometric frequency control.

Anselm J Deninger¹, Thorsten Göbel, Daniel Schönherr

¹TOPTICA Photonics AG, Lochhamer Schlag 19, D-82166 Gräfelfing, Germany.

The Review of Scientific Instruments

|May 2, 2008

Summary

We developed a tunable terahertz source with megahertz frequency resolution using stabilized diode lasers and optical heterodyning. This breakthrough enables high-resolution terahertz spectroscopy for advanced material characterization.

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Generation and Coherent Control of Pulsed Quantum Frequency Combs

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Design, Fabrication, and Experimental Characterization of Plasmonic Photoconductive Terahertz Emitters

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Terahertz Microfluidic Sensing Using a Parallel-plate Waveguide Sensor

Terahertz Microfluidic Sensing Using a Parallel-plate Waveguide Sensor

Published on: August 30, 2012

Area of Science:

Physics
Spectroscopy
Optics

Background:

Precise terahertz (THz) sources are crucial for advanced spectroscopy.
Existing THz generation methods often lack sufficient tunability and frequency resolution.
Optical heterodyning offers a promising route for generating coherent THz radiation.

Purpose of the Study:

To develop a continuously tunable terahertz source with megahertz frequency resolution.
To demonstrate the capability of this source for high-resolution terahertz spectroscopy.
To characterize the transmission properties of a subwavelength metal grating using the developed system.

Main Methods:

Utilizing optical heterodyning of two stabilized near-infrared distributed feedback diode lasers.
Employing electronic feedback from a low-finesse quadrature interferometer for laser stabilization.
Implementing precisely linear laser frequency scans over a >1200 GHz range.
Using Gallium Arsenide (GaAs) photomixers and log-periodic antennae for THz detection.

Main Results:

Achieved a beat signal linewidth of 1 MHz at an 80 ms time scale.
Obtained a signal-to-noise ratio (SNR) of >70 dB at 100 GHz and 100 ms integration time.
Maintained an SNR of approximately 30 dB at 1 THz.
Successfully characterized the transmission of a subwavelength metal grating, demonstrating high-resolution spectroscopy.

Conclusions:

The developed tunable continuous-wave terahertz source offers unprecedented megahertz frequency resolution.
The system enables high-performance terahertz spectroscopy, suitable for characterizing complex materials.
This technology advances the field of terahertz science and its applications in material analysis.