Search for: All records

Mid-infrared semiconductor lasers have a wide range of applications in gas sensing, environmental monitoring, medical diagnosis and other fields. The V-coupled cavity laser (VCCL) approach has been successfully applied in the communication band to achieve single-mode operation with a wide tuning range because of its advantages of no grating, compact structure and simple wavelength control. In this paper, the concept of V-coupled cavity is introduced to the interband cascaded lasers, and a monolithically integrated mid-infrared widely tunable single-mode laser is developed. In addition, we experimentally demonstrated a simple and general algorithm for wavelength tuning controlled by two electrodes synchronously, and realized quasi-continuous tuning of single-mode wavelength in mid-infrared interband cascade laser based on the V-coupled cavity configuration for the first time. In the tuning process, the injection current of the short cavity remains unchanged, and the stepped increase of the long cavity current is equivalent to the realization of discrete tuning with the channel spacing of 1.1 nm determined by the short cavity. With the increase of the injection current of the coupler electrode while fixing the long cavity current, the thermo-optic effect caused by the coupler current will cause the refractive index of the two FP cavities to change together, thus realizing the fine tuning of the laser wavelength. A total tuning range of 53.2 nm has been achieved, from 2.8244 μm to 2.8776 μm, with the temperature adjusted from 110K to 120K.