Large single crystal growth of MnWO4-type materials from high-temperature solutions

• Construction of a cost-efficient crystal growth apparatus.
• Large single crystal growth of (In, Na): MnWO4-solid-solution compounds.
• Polar symmetry of their atomistic structures.
• Epitaxial growth of (In, Na): MnWO4 on MnWO4.

A simple high-temperature growth apparatus was constructed to obtain large crystals of chemically gradient (In, Na)-doped MnWO4solid-solutions. This paper presents the crystal growth and characterisation of both MnWO4and epitaxially grown (In, Na): MnWO4crystals on MnWO4. These large monolithic crystals were made in two steps: A MnWO4 crystal was grown in the crystallographic main direction [001] applying the Czochralski method, followed by the top seeded growth of (In, Na): MnWO4 solid-solutions with an oriented seed crystal of MnWO4. Such a monolithic crystal will serve to fundamental investigation of coupling properties at boundaries between various multiferroic MnWO4-typesolid-solutions.