Growth, optical and electromechanical properties of single-crystalline orthorhombic bismuth triborate

Orthorhombic bismuth triborate (δ-BiB3O6) single crystals were grown via the top-seeded method at atmospheric pressure. δ-BiB3O6 is shown to be a stable polymorph at temperatures close to the melting point while α-BiB3O6 is a metastable one. Optical, acoustic and electromechanical properties of δ-BiB3O6 are measured. Possibility of doping δ-BiB3O6 with large amounts of rare earths is demonstrated.