Tunability of a microchip Yb:KGW solid-state laser self-injected with different wavelength-selective external cavities

Abstract This work investigates tunable emission in a continuous-wave Yb:KGW microchip-type solid-state laser utilizing an external cavity. While microchip lasers offer advantages like compactness and simplicity, achieving broad tunability within the compact laser structure presents challenges. The influence of crystal position relative to the pump on the emission polarization was explored. To achieve pump-independent tuning, two external cavity configurations were implemented, including a Littrow configuration with a diffraction grating and a configuration employing a bandpass filter. The filter-based configuration demonstrated superior performance, enabling a tuning range exceeding 35 nm. The obtained results demonstrate the potential of external cavity techniques to enhance the tunability and performance of microchip lasers for applications requiring wavelength-agile sources.