METHOD OF PRODUCING SINGLE CRYSTAL

摘要

PROBLEM TO BE SOLVED: To provide a method of producing a single crystal by which a high quality lithium tetraborate single crystal containing an impurity element added and having high light transmittance is produced. SOLUTION: The method of producing the Li2 Br4 O7 single crystal to which an impurity element is added includes the following processes: a) oxide raw materials having a predetermined composition are mixed and the resulting mixture is heated to a temperature of >=1,000 deg.C so as to melt the mixture in a crucible; b) a raw material for growing the single crystal is produced by pouring the melt into a casting mold and solidifying the melt; and c) the single crystal is formed by crystallizing the raw material for growing the single crystal by a Bridgman method or a Czohralski method.