Laser crystal of sodium tungstate with waveband of 2 microns

Abstract

The invention provides a laser crystal of sodium tungstate with waveband of 2 microns, belonging to a tetragonal system. The laser outputting the waveband of 2 microns has the characteristics of shortgrowth period, good integrality, high crystal yield, low threshold, high gain and the like. The prepared laser has high laser output efficiency and belongs to the field of photoelectron materials. The existing laser crystal of kalium and rare-earth compounded tungstate, mixed with rare-earth activated ion, has long growth period; furthermore, the laser crystal of rare-earth salt vanadate, mixed with the rare-earth activated ion, has the growing raw material with high melting point, thus easily causing segregation due to volatilization; and the grown crystal has bad thermal performance, is easy to crack and has colored core. The laser crystal is mixed with the rare-earth activated ion with the waveband of 2 microns, and the substrate is sodium and rare-earth compounded tungstate. The lasercrystal is applied to the fields such as distance measurement by laser, lidar, photoelectric interference, remote sensing, environmental detection, optical communication, medical treatment and the like.

Description

technical field [0001] The invention relates to a 2μm sodium tungstate laser crystal, which belongs to the tetragonal crystal system and outputs laser light in the 2μm band. It has the characteristics of short growth period, good integrity, high crystallization rate, low threshold value, and high gain. The produced laser The laser has high output efficiency and belongs to the field of optoelectronic materials. Background technique [0002] The laser in the 2μm band has the characteristics of good atmospheric transmission characteristics, strong smoke penetration ability, and good confidentiality. It is used in laser ranging, lidar, photoelectric interference, remote sensing, environmental detection, optical communication and other fields. In addition, the laser in the 2μm band has strong absorption in water, so it is not only safe for human eyes, but also can accurately intervene in biological tissues, and has application value in medical fields such as ophthalmic surgery. ...

AI Technical Summary

Problems solved by technology

The existing laser crystals capable of producing such lasers are potassium and rare earth compound tungstates doped with rare earth activating ions, such as Ho:KGW, Ho:KYW, Ho:Yb:KGW, Tm:Ho:KGW, etc. The crystalloid belongs to the monoclinic system and is grown by the top seed crystal pulling method. In order to avoid the phase transition during the growth process, it is necessary to add a flux to the melt so that the growth process proceeds at the phase transition temperature. However, this The measures lead to the reduction of solute in the melt, so the growth rate slows down and the growth cycle is long, such as the growth size is 25×25×15mm 3 Laser crystals with a growth rate of 1-2mm / d and a growth period of 10-15d

The other type is rare earth vanadate doped with rare earth activating ions, such as Ho:YVO 4 、Ho:GdVO 4 , this type of crystal belongs to the tetragonal crystal system, and there is no phase transition during the growth process. Therefore, compared with the monoclinic crystal system, the growth rate is high and the cycle is short. However, the growth raw material has a high melting point and is prone to segregation due to volatilization. The grown crystals have poor thermal properties, are easy to crack, and have colored centers.