Terahertz quantum cascade laser frequency combs with engineered operation frequency around 4.0 THz
Shumin Wu,
Kang Zhou,
Ziping Li,
Xuhong Ma,
Chenjie Wang,
Binbin Liu,
Wenjian Wan,
Zhenzhen Zhang,
Hua Li
Affiliations
Shumin Wu
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Kang Zhou
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Ziping Li
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Xuhong Ma
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Chenjie Wang
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Binbin Liu
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Wenjian Wan
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Zhenzhen Zhang
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Hua Li
National Key Laboratory of Materials for Integrated Circuits and Key Laboratory of Terahertz Solid State Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai 200050, China
Freely engineering the operation frequency of frequency comb sources is crucial for various applications, e.g., high-precision spectroscopy, ranging, communications, and so on. Here, by employing band structure simulations, group velocity dispersion (GVD) analysis, and experimental verifications, we demonstrate that the operation frequency of terahertz (THz) quantum cascade laser frequency combs can be engineered from 4.2 to 4.0 THz. First of all, from the viewpoint of the band structure engineering, we shift the frequency corresponding to the optical transitions in the active region from 4.2 to 4.0 THz by slightly altering the thicknesses of quantum wells. Meanwhile, a GVD analysis is applied to evaluate the potential comb performance. Finally, experimental characterizations, e.g., emission spectra, inter-mode beatnote, dual-comb operation, are performed to validate the exceptional comb operation at 4.0 THz. The advancement in simulations and experimental results present a comprehensive method to customize the desired THz radiative frequency for comb generation, which facilitates the practical development of broadband, high-precision THz comb sources.
