Abstract

The merit of Yb³⁺-doped fluorapatite (Ca₅(PO₄)₃F or Yb:FAP)¹ lies in the potential for direct laser diode pumping owing to its high efficiency, low threshold power and its absorption band at 904-nm which is readily available from InGaAs laser diodes. In this paper we report the observation of lasing of Yb:FAP at the 981-nm line, which is believed to be lasing to the ground state level. Furthermore by careful choice of optics, the crystal was made to lase on the 981 and the 1042-nm lines either singly or simultaneously. The 981-nm laser emission was polarized perpendicular to the c-axis of the crystal whilst the 1042-nm emission was polarized parallel to the c-axis.

© 1993 Optical Society of America