Optical isolator

An optical isolator, or optical diode, is an optical component which allows the transmission of light in only one direction. It is typically used to prevent unwanted feedback into an optical oscillator, such as a laser cavity.

The operation of conventional optical isolators relies on the Faraday effect (which in turn is produced by magneto-optic effect), which is used in the main component, the Faraday rotator. However, integrated isolators which do not rely on magnetism have been made in recent years too.^[1]

^ White, Alexander D.; Ahn, Geun Ho; Gasse, Kasper Van; Yang, Ki Youl; Chang, Lin; Bowers, John E.; Vučković, Jelena (February 2023). "Integrated passive nonlinear optical isolators". Nature Photonics. 17 (2): 143–149. doi:10.1038/s41566-022-01110-y.

[1] White, Alexander D.; Ahn, Geun Ho; Gasse, Kasper Van; Yang, Ki Youl; Chang, Lin; Bowers, John E.; Vučković, Jelena (February 2023). "Integrated passive nonlinear optical isolators". Nature Photonics. 17 (2): 143–149. doi:10.1038/s41566-022-01110-y.

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