GeO₂ crystals, which are isostructural to quartz (SiO₂), are grown at Institut Néel by a high temperature flux method . It is one of the promising piezoelectric materials to be used for high temperature applications and in nonlinear optical devices.

Single crystals, such as KH2PO4 (fig. 1a), are central to many fields of science and industry. From all the techniques used to obtain them, growth from solution remains one of the most efficient synthesis route for synthetic crystalline solids in research laboratories and in the related industry.