NEODYMIUM ALUMIUM TETRABORATE CRYSTAL AND MINIATURE ALL SOLID STATE LASERS

The development of all solid state lasers towards the high power and miniature products have been receiving general interests.The disk-type all solid state lasers can offer laser beams of kW in power,while the microchip lasers are favored because of their small volume and high efficiency/high density for medium/low power output.It is well known that high quality laser crystals are the pre-requisites for fabricating high performance lasers.In this article,we summarize the state-of-art of self-activated laser crystals including detailed description of their structures,properties,and performances,based on the requirements for miniature laser applications.Particular attentions are paid to neodymium aluminum tetraborate(NdAl3(BO3)4,one of the typical and also best self-activated laser crystals.We highlight the main results of investigation on the structure,growth process,and performances of NdAl3(BO3)4,as well as its potential applications in miniature lasers.Recently,a 1.064 μm laser beam output of 4.6 W in power and 64% in slop efficiency,using a 4×4×0.39 mm3 NdAl3(BO3)4 disk crystal pumped with a 883 nm LD laser,has been reported,demonstrating the promising potential of NdAl3(BO3)4 as self-activated laser crystal in miniature lasers.