Power scaling of diode-pumped Nd(3+) and Yb(3+)-Doped YCa(4)O(BO(3))(3) (YCOB): A new self-frequency doubling laser.

摘要

Intracavity-doubled, diode-pumped solid-state lasers are rapidly gaining acceptance in manufacturing, medical and scientific applications. The reasons for this intense development include their high efficiency, diffraction-limited beam quality, and long lifetimes. Moreover, a compact, low cost, rugged package design makes these systems attractive. The different approaches to intracavity frequency doubling of infrared laser radiation using birefringent phase-matching have generally included a nonlinear crystal that is separated from the laser medium to generate efficient continuous-wave visible light. A special case of intracavity-doubling known as self-frequency doubling in conjunction with diode-pumping offers the potential for a simpler, more compact and low cost design by integrating the laser and harmonic conversion process in one crystal.; A comprehensive study of the operation and power scaling abilities of the newly developed crystal YCa₄O(BO₃)₃ (YCOB)—doped with either Nd3+ or Yb3+ for self-frequency doubling is performed. Laser operation and self-frequency doubling is achieved under flashlamp, Ti:Sapphire, and diode-pumping. High power diode-pumped operation of Nd3+:YCOB using a novel angularly-multiplexed diode-laser system for power scaling demonstrates more than 1.9 W at 1060 nm and over 245 mW at 530 nm. In addition, analysis of thermal-fracturing of Nd 3+:YCOB suggests a thermal fracture figure-of-merit of ∼247 W/m for Nd3+:YCOB. Diode-pumped operation at 977 nm of Yb 3+:YCOB has demonstrated slope efficiencies of better than 40% with operation from 1030 to 1090 nm.