A compact optical isolator using a Y3Fe5O12crystal for near infra-red radiation

摘要

Using a Y3Fe5O12crystal as a Faraday rotator material, a samarium cobalt permanent magnet and two iron yokes, a compact optical isolator was constructed at 1.153μm for optical transmission systems. The developed isolator is 13 mm in diameter and 25 mm in length, including two polarizers. The isolator characteristics are 1.3 dB forward loss and greater than 30 dB backward loss. A broadband isolator is realized by inserting a 45 degree Faraday rotator and an optically active 45 degree quartz rotator between the two polarizers set at 90 degrees in relation to each other