Intracavity spatial mode conversion by mean of holographic phase masks

The engineering of spatial modes via conventional methods of phase transformation can only be efficiently achieved at a specific wavelength due to the monochromatic nature of a complex phase profile. Nevertheless, holographic phase masks – i.e. complex phase structures coupled with the transmissive volume Bragg grating, possess a high degree of tunability and achromatism. Such complex phase elements, holographically recorded in the volume of photo-thermo-refractive glass, allow them to withstand high average-power operating conditions uniquely suited for intra-cavity mode conversion. Here we demonstrate a linear, wavelength-tunable, continuous-wave Yb3+:KYW laser capable of emitting customizable spatial modes by mean of holographic phase masks.