摘要 |
1,149,492. Lithium niobate. WESTERN ELECTRIC CO. Inc. 7 July, 1966 [12 July, 1965], No. 30535/66. Heading C1A. [Also in Division B1] A lithium niobate crystal is treated by passing an electrical current through at least a portion of it whilst this portion is maintained at a temperature of at least 1000‹ C. Alternatively, a lithium niobate crystal is grown by pulling from a melt and an electrical current is passed through the crystal and through the interface between the growing crystal and the melt. The current density is at least 0À1 ma/cm<SP>2</SP>. when treating the crystal alone and at least 0À5 ma/cm.<SP>2</SP> when using the melt. The treatment is said to influence the formation of magnetic domains in the crystal and a reversal of current during the treatment produces a second magnetic domain. The current may be reversed several times during the treatment to produce a series of domains. |