Design and implementation of mode-locked external fiber-based resonator for quantum dot semiconductor laser for solid-state quantum systems

Quantum dot-based single-photon sources are essential for photonic quantum technologies. For efficient operation, it is crucial to utilize pulsed lasers with properties tailored to quantum dots. We present the application of mode-coupled high-power laser systems with an external resonator. This approach offers several advantages, including the ability to significantly increase the resonator length, which enhances performance. To achieve this, a fiber with a Fiber Bragg grating is coupled to the semiconductor laser, substantially increasing the resonator length. For efficient fiber coupling an optical design study was conducted with the result of using a lensed fiber. Furthermore, we designed and implemented a compact optomechanical package that includes a thermal management system for the laser. Given the highly critical alignment tolerances, we present an active alignment setup to couple the polarization-maintaining lensed fiber to the semiconductor laser.