Crystal growth and characterization of YAlO_3 single crystals, doped with rare earth ions, esp. Nd, Er for laser applications. Einkristallzuechung und Charakterisierung von YAlO_3-Kristallen dotiert mit seltenen Erden, insbesondere Nd, Er fuer Laseranwendungen Final report/Abschlussbericht

According to A. Kaminski [1] 280 laser hosts and 24 activators have been known. The yttrium aluminium perovskite YAlO_3 (YAP) laser crystal belong to the most widely used laser hosts and the Nd, Tm, Er ions are the most wide spread activators [2-4]. Laser on the basis of YAP-Nd allow to obtain a continues wave power up to 424 W (efficiency #eta##propor to#2.54%) at #lambda#=1.079 #mu#m, and 195.8 W (#eta##propor to#1.43%) at #lambda#=1.34 #mu#m as well as energy of pulses in some tenths of joules in the free generation mode [5,6]. YAP-Nd-based active media have a number of advantages in comparison with Nd-doped yttrium aluminium garnet (YAG) single crystals [6-8]. Some of them are listed below: (1) YAP melting temperature (about 1900 C) is 70 C below that of YAG, and the pulling rate is 3-5 times higher; (2) a larger Nd segregation coefficient in YAP (0.8 in comparison with 0.18 for YAG) permits a higher doping level; (3) a possibility of forming shorter generation pulses; (4) highly polarized radiation at fundamental wavelength and high efficiency conversion to the second and third harmonics can be obtained due to optical anisotropy of YAP single crystals; (5) the integral absorption cross-section for YAP-Nd in the pumping band exceeds that of YAG, and the YAP laser transition cross-section at #lambda#=1.34 #mu#m (#sigma#2.2 x 10"-"1"9 cm"2) is twice larger that of YAG. (orig.)SIGLEAvailable from TIB Hannover: F00B381 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung und Forschung (BMBF), Bonn (Germany)DEGerman