Project Details
Projekt
Terahertz Injection Locking of Quantum Cascade Lasers using Modified Uni-Travelling Carrier Photodiodes (UTC4QCL)
Applicants
Johanna Böhm, Ph.D.; Professor Dr. Heinz-Wilhelm Hübers; Dr. Xiang Lü; Professor Dr.-Ing. Andreas Stöhr
Subject Area
Communication Technology and Networks, High-Frequency Technology and Photonic Systems, Signal Processing and Machine Learning for Information Technology
Term
since 2024
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 550747769
Phase-resolved high-precision terahertz (THz) atmospheric and astronomical gas spectroscopy necessitates the use of local oscillators (LOs) operating in the frequency range between 2-5 THz. High resolution and accuracy of the measurements require a narrow linewidth and stable THz LO source. The most versatile and promising laser source in this spectral range is the THz quantum cascade laser (QCL). The intrinsic linewidth of the THz QCL is of the order of a few hundreds of Hz but thermal, electrical, and mechanical instabilities typically result in free-running linewidths of a few MHz. This has led to the development of several techniques to stabilize the frequency of QCLs which only make use of an electrical feedback to stabilize the frequency of the QCL to a stable reference source. A significant drawback of this technique is that the bandwidth over which the frequency fluctuations can be compensated is limited. Aim of the proposed project is the development of a THz injection locking of QCLs using modified uni-travelling carrier photodiodes (MUTC-PDs). Within the framework of this project the usage of MUTC-PDs operated at room temperature as well as at cryogenic temperatures is investigated.
DFG Programme
Priority Programmes
International Connection
United Kingdom
Cooperation Partners
Dr. Martyn Fice; Professor Dr. Joshua Freeman
