On the feasibility of growing Ca5(BO3)3F fiber crystals by the micro-pulling down technique using a LiF-based flux

Compact all solid-state lasers emitting in the ultraviolet range are more and more required for numerous applications such as materials processing, micromachining,photolithography, sensors for the detection of gaseous pollutants, or in biology and medicine. In this frame, single crystals allowing the generation of a UV radiation by frequency conversion of an infrared one are promising materials. Crystals of the borate family and especially fluoroborates are good candidates as the new compound Ca5(BO3)3F (CBF) which is chemically stable and not hygroscopic. Bulk single crystals were very recently grown for the first time by a flux method from the CBF-LiF system [1, 2]. The growth of good quality single-crystal fibers could be very advantageous for the miniaturization of devices. In this paper, we shall report on the first growth and characterization of such crystal fibers using the micro-pulling down technique (µ-PD)