Growth and characterisation of monoclinic KGd1−xREx(WO4)2 single crystals

Abstract The high-temperature solution growth of KGd(WO 4 ) 2 single crystals doped with trivalent rare earth (RE 3+ ) ions has been investigated by using the top seeded solution growth (TSSG) technique and K 2 W 2 O 7 as solvent. Electron probe microanalyses were used to determine the RE concentration in the crystals grown. For the 1% doping level in the melt the distribution coefficients of Nd, Er, Ho and Tm are in the 0.8–1.1 range. Yb and Pr have smaller distribution coefficients of 0.7 and 0.5, respectively. The crystal field splittings of the Ho 3+ , Er 3+ and Yb 3+ electronic multiplets have been determined at 4.2 K. Some evidence of the presence of several Yb 3+ centres has been obtained.