We present unique spatial-mode switching in a cw Yb:CALGO laser when pumped at a multihundred-watts power level. It permits us to automatically stabilize to a TEM(00) mode from a highly spatial multimode regime. This stabilization is achievable thanks to polarization-mode switching allowed by the particular spectroscopic and thermal properties of Yb:CALGO crystal. This atypical and unexpected behavior is studied in detail in this Letter and explained by analysis of the thermo-optical coefficients for CALGO.

No abstract

We present some anisotropy properties of the Yb:CALGO with a spatial mode switching when pumped in the multihundred watts of power. This allows to automatically stabilize a TEM 00 mode from highly spatial-multimode regime. This stabilization is achievable thanks to a polarization mode switching allowed by the particular anisotropic spectroscopy and thermal properties of Yb:CALGO.

Aeolus is operating in-flight since more than 4 years and has generated 6.4 billion UV laser shots. The progressive received signal decrease was recently partially compensated by switching laser A on, allowing extending mission lifetime.