Characterization of dislocations and sub-grain boundaries in mixed rare earth orthovanadate of Yb:YxLu1−xVO4

•A new mixed crystal of Yb:Y0.71Lu0.29VO4s was grown by Czochralski method.•The dominating defects are block structures, dislocations and sub-grain boundaries.•Edge dislocations with Burgers vectors of 〈100〉 were found in grown crystal. Mixed crystal of Yb:YxLu1−xVO4 was grown by Czochralski method. Defects of dislocations and sub-grain boundaries in Yb:Y0.71Lu0.29VO4 single crystal were studied by using chemical etching and synchrotron X-ray topographic methods. Some of the three intersecting boundaries were revealed by chemical etching method in Yb:Y0.71Lu0.29VO4 crystal. The generalized Read–Shockley formula for intersecting boundaries was introduced to verify the one-to-one correspondence between etching pits along these sub-boundaries and edge dislocations with Burgers vectors of 〈100〉. Synchrotron X-ray topographic confirmed that the dominating imperfections in the studied Yb:Y0.71Lu0.29VO4 single crystal are a variously developed block structure and sub-grain boundaries.