Apparatus comprising a magneto-optic isolator utilizing a garnet layer.

摘要

Apparatus according to the invention comprises magneto-optic isolator means that utilize a novel temperature compensation scheme. The scheme involves the use of a composite magneto-optic member (60) that comprises a substrate (61), a first single crystal garnet layer (63) that does not have a compensation temperature within the operating temperature range of the isolator, and further comprises a single crystal garnet layer (the "compensation point layer") (62) that has a compensation temperature within the operating temperature range of the isolator. Exemplarily, the compensation point layer has composition (Bi0.8Tb1.1Gd1.1)(Fe4.6Ga0.4)O12, and is grown on an CMZ:GGG substrate, and the first garnet layer has composition (Bi1.2Tb1.8)(Fe4.6Ga0.4)O12 and is grown on the compensation point layer. The novel temperature compensation scheme can result in isolators having improved extinction ratio with relatively small additional path length in the magneto-optic material.