Mitigation strategies for depolarisation effects of ultrashort pulse written fused silica VBGs

In recent decades, VBGs have received increasing interest due to their outstanding properties: They have been used as narrow-band filters, to achieve excellent spectral stabilisation of laser diodes and to replace large-volume compressors in CPA systems with a single compact element [1]. However, these optical elements are typically restricted to a specific glass due to their manufacturing process. Using ultrashort laser pulses, these material restrictions can be overcome. This allows selecting the glass material optimal for the specific application [2]. As an example, the use of fused silica is attractive for high power laser applications due to its high purity and very low absorption.