1.State Key Laboratory of Luminescence and Application， Changchun Institute of Optics， Fine Mechanics and Physics， Chinese Academy of Sciences， Changchun 130033， China;2.Center of Materials Science and Optoelectronics Engineering， University of Chinese Academy of Sciences， Beijing 100049， China;3.School of Physics， Beihang University， Beijing 100191， China
Supported in part by the National Key Research and Development Program （2020YFC2200300）， in part by the National Natural Science Foundation of China （11774343， 51672264， 61874119， 61874117）， in part by the Science and Technology Development Project of Jilin Province （20200401006GX）.
We design and fabricate a double-wavelength tunable laser with a single grating structure using a single-gain chip. The gain chip adopts an indium-rich cluster quantum constraint structure， which can generate ultra-wide flat-top gain. The flat-top gain is the basis for producing a dual-wavelength laser with the same intensity. A grating is inserted into the exterior of the gain chip so that its resonator is composed of internal and external cavities. The internal cavity consists of two natural cleavage planes of the gain chip for oscillating the output laser at a fixed wavelength （974 nm）. The tunable external cavity consists of a natural cleavage plane and a grating for the output laser at a tunable wavelength （969.1~977.9 nm）. The laser structures of the single-gain chip and single grating can produce synchronous dual-wavelength output， which avoids a complicated optical path design. The frequency difference between the two wavelengths is in the terahertz band. Thus， the laser can be used as a dual-wavelength laser source to generate terahertz radiation.
LI Xue, TAI Han-Xu, WANG Yu-Hong, ZHENG Ming, ZHANG Jian-Wei, ZHANG Xing, NING Yong-Qiang, WU Jian, WANG Li-Jun. Tunable dual-wavelength semiconductor laser based on indium-rich cluster quantum structure[J]. Journal of Infrared and Millimeter Waves,2022,41(3):540~544Copy