We report efficient second harmonic conversion in a new nonlinear opti
cal crystal, Yb3+ doped YCa4O(BO3)(3), that is non-hygroscopic, has go
od optical and mechanical properties, and can be grown in large sizes.
The effect of Yb concentration on the harmonic conversion efficiency
is also investigated. (C) 1998 Elsevier Science B.V. All rights reserv
ed.