Faraday rotator optical interconnects for optical insulator in semiconductor substrate packaging

An photonics package, comprising:

• a photonics die embedded in a package substrate:
• an opening in the package substrate to expose a surface of the photonics die;
• a lens over the exposed surface the photonics die;
• and
• a Faraday rotator attached to the package substrate over the lens.

An electronic system, comprising:

• a board;
• a package substrate over the board;
• a photonics die over the package substrate;
• a compute die over the package substrate, wherein the compute die is communicatively coupled to the photonics die by a bridge embedded in the package substrate;
• an integrated heat spreader (IHS) over the package substrate;
• and
• a Faraday rotator passing through the IHS and optically coupled to the photonics die.